UNIFIED MESSAGING FIELD OF THE INVENTION The present invention is related to a method of retrieving and distributing voice messages from a voice mail system. BACKGROUND OF THE INVENTION Mobile telephone companies generally directly support a specific geographical region, for example a country like Israel, which is supported by the mobile telephone company's infrastructure. Telephone conversations with users (or originating from users) located outside this region tend to be expensive since they require routing through another company's infrastructure. Some companies charge the mobile telephone user for the difference between a local call in their region and a call outside their region. A user can choose not to receive calls while out of the region and let callers leave voice messages, thereby eliminating the extra charges. However a user that wishes to hear the messages while outside the region will need to call the mobile telephone supplier and pay a high rate for this conversation. In addition, retrieving messages takes more time than just listening to the messages, since the process requires the user to make selections from options verbally spoken to the user at a pace set by the telephone company. In US patent publication 2001/0039561 to Cho, the disclosure of which is incorporated herein by reference, there is described a method of emailing messages received by a voice mail system to the user and sending an SMS message to notify that messages were sent. This system requires the involvement of the telephone company in order to willfully transfer messages from the voice mail system to the email server. In many cases the telephone companies are not interested in such an involvement since a considerable portion of their profits are derived from voice mail systems and message retrieval. In US patent 5,943,398 to Klein et al., the disclosure of which is incorporated herein by reference, there is described a system which performs automatic message translation of the contents of a user's mailbox from voice to text and vice versa. SUMMARY OF THE INVENTION An aspect of some embodiments of the invention relates to a method of locally retrieving voice mail messages for various users for example a user located out of the local region of a telephone company, and transmitting them to the user by other methods, for example by non voice calling methods. Optionally, the other methods are more economically feasible and/or more convenient to the user, for example Email or SMS. Optionally, a call back service is used to call up the user with the messages. In some embodiments of the invention, a server located in the local region of the telephone company initiates a call to the voice mail server and automatically records the user's messages. Optionally, the messages are saved in a standard format, such as WAV or MP3, in order to be transmitted by the other methods (e.g., more economical) to the user. In some embodiments of the invention, the messages are Emailed to an Email address of the user. In another embodiment of the invention, the messages are sent by SMS, MMS or other data messaging system to the user, for example as a "ringtone" message. In another embodiment of the invention, the messages are stored at an Internet accessible web site and can be retrieved by the user. In some embodiments of the invention, the messages are retrieved periodically at an interval set by the user when initiating the retrieval service. Optionally, the interval can be changed by the user for example by sending an Email or SMS to the server or accessing a web page, to select the value. Alternatively or additionally, the retrieval service can be initiated by a notification from the user, for example by sending an Email, SMS message, notifying on a web page or by calling up a number. In an exemplary embodiment of the invention, messages are downloaded from a voice mail system with the server identifying tones sounded by the voice mail system. In one example, message content delimiter tones are identified. In another example, an "end of messages" tone is recognized. There is thus provided in accordance with an exemplary embodiment of the invention, a method of automatically rerouting voice mail messages using a server computer comprising: voice calling a voice mail server, by the server computer; retrieving a user's voice mail messages, by the server computer; transmitting the retrieved messages to the user by a communication method selected by the user. Optionally, the calling is performed in response to a request from the user. Alternatively, the calling is performed at specific hours. Alternatively, the calling is performed at specific time intervals. Optionally, the retrieving comprises supplying a user password. Alternatively or additionally, the retrieving comprises deciphering voice messages. Alternatively or additionally, the retrieving comprises recording the voice mail messages. Alternatively or additionally, the retrieving comprises encoding the voice mail messages in a standard encoded voice file format. Alternatively or additionally, the retrieving is limited to a maximum number of messages. Optionally, the transmitting is in response to a request from the user. Alternatively or additionally, the retrieved messages are transmitted to a users Email address. Alternatively or additionally, the retrieved messages are transmitted to a web site accessible to the user. Alternatively or additionally, the retrieved messages are transmitted as voice messages to a user using SMS. Alternatively or additionally, the retrieved messages are translated from voice to text and transmitted as SMS messages to a user using SMS. Alternatively or additionally, the number of messages transmitted to a user is limited by a maximum number. Optionally, the method further comprises notifying the user of the number of messages before the user selects the method of transmission. Alternatively or additionally, the method further comprises notifying the user of the telephone numbers supplied with the messages prior to transmitting the messages to the user. Alternatively or additionally, the user selects the messages to be transmitted. In an exemplary embodiment of the invention, said retrieving comprises identifying tones produces by said voice mail system. BRIEF DESCRIPTION OF THE DRAWINGS Non limiting embodiments of the invention will be described with reference to the following description of exemplary embodiments, in conjunction with the figures. The figures are generally not shown to scale and any measurements are only meant to be exemplary and not necessarily limiting. Identical structures, elements or parts which appear in more than one figure are preferably labeled with a same or similar number in all the figures in which they appear. Fig. 1 is a schematic illustration of a voice message retrieval and distribution system in accordance with an exemplary embodiment of the invention; Fig. 2 is a flowchart of the system according to an exemplary embodiment of the invention; and Fig. 3 is a flowchart of the retrieval process according to an exemplary embodiment of the invention. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS Fig. 1 is a schematic illustration of a voice message retrieval and distribution system 100 according to an exemplary embodiment of the invention. System 100 comprises a server computer 110, which performs message retrieval for mobile telephone users 140 and transmits them the messages using methods other than voice retrieval. Optionally, the other methods are more economical methods and/or more comfortable methods as will be described below. Server 110 can be one or more computers and is optionally parts of a distributed network of servers. In some embodiments of the invention, server 110 is connected to the Internet 130, for example to send and receive Emails and/or manage a resident web site or communicate with a web site hosted on other servers. Optionally, a user can join the distribution service by signing up at the web site, supplying their mobile telephone number, password (e.g., for system and/or for voice mail), credit card number, voice mail server details, and/or other optional details. Alternatively or additionally, a user can sign up by sending the information by Email. Further alternatively or additionally, a user can sign up using an automated answering service (e.g. IVR-interactive voice response), by sending an SMS message and/or by giving his or her details to a human sales representative. In some embodiments of the invention, server 110 keeps a list of the mobile telephone users 140 and their details and optionally, allows the users to update their details using one or more of the methods of communication described above for signing up. One or more of these methods may be used for controlling the behavior of server 110, for example as described below. In an exemplary embodiment of the invention, server 110 comprises a modem and/or a - DTMF card and/or a voice recognition program, which are used to contact and/or communicate with a voice message retrieval service 120 supplied by the mobile telephone company. Optionally, server 1 10 is programmed to know what to respond by knowing the questions and their order for a specific mobile telephone company. When server 110 detects a pause it provides the correct tone response. Alternatively or additionally, server 110 compares the received voice message with a list of known voice messages in order to decipher the message. In some embodiments of the invention, the voice recognition program deciphers the voice message retrieval service commands and transmit the necessary tone codes responsive to the instructions given. In an exemplary embodiment of the invention, server 110 is programmed with a plurality of scripts, one for each type of voice mail system it is to work with. For example, different voice mail systems may use different key commands, sound different instructions, have different delays associated with them and/or use different enunciator sounds. Programming methods other than scripts, for example state tables, may be used. Optionally, the scripts are hand coded. Alternatively, server 1 10 may learn the behavior of a voice mail system. Optionally, even for a same voice mail system the execution of a script for two users may be different. For example, one user may request to delete downloaded messages, while another requests to keep such messages on the server. In another example, a user may specifically request to hear "stored" messages. In an exemplary embodiment of the invention, server 1 10 identifies tones used by the system, fro example, start of message, end of message and end of messages tones. Optionally, these tones are sampled from the voice mail system and then used as a template for recognition. Alternatively, such tones may be identified based on their spectral properties. Optionally, speech output by the voice mail system is recognized not as speech messages, but using patent recognition, for example, based on sampling and identifying spectral properties that are unique for each message. Optionally, the user indicates to server 110 which voice mail system he is using and/or various parameters, for example the language. Alternatively, the voice mail system may be identified automatically, for example based on the service provider, telephone number used (e.g., for non telephone company voice mail systems, such as office and home systems) and/or by identifying the language. Various language identification, speech identification and speech processing methods are known in the art and may be used. In some embodiments of the invention, server 110 is connected to an SMS (short message service) transmitter in order to send SMS messages to mobile telephones. Alternatively or additionally, server 110 sends SMS messages using other means, such as via the Internet 130 or by transmitting the messages to an SMS message broadcast service using other mediums such as a dial up connection or a leased line. In some embodiments of the invention, server 1 10 is connected over a network with other computers and the various tasks are distributed among the computers of the network. For example one computer runs the web site, a different computer maintains the user list and other computers deal with collecting messages and distributing them, for example, as will be described below. Fig. 2 is a flowchart 200 of a primary service performed by system 100 for mobile telephone users 140 according to an exemplary embodiment of the invention. In some embodiments of the invention, a mobile telephone user 140 contacts (210) server 110 in order to request server 110 to retrieve his or her voice messages from a mobile telephone voice message service 120. Optionally the notification is performed by accessing the servers web site and/or sending an Email message to server 110. Alternatively or additionally, the notification is performed by sending an SMS message to server 1 10. Further alternatively or additionally when the user signs up, the user may select the hours and/or time interval at which server 1 10 should perform message retrieval. Optionally, these values can be updated with a new value by methods such as those suggested above. In some cases, the mobile telephone company sends the user a notification for example by SMS or Email when there are pending messages. In an exemplary embodiment of the invention, such a notification is redirected to server 110 in order for server 110 to automatically retrieve the messages. In an exemplary embodiment of the invention, (210) upon receiving a request from mobile user 140 as described above, server 110 performs (220) the process of retrieving the user's messages from the mobile telephone company that serves the user. Fig. 3 is a flowchart of the process of retrieving (220) the user's messages according to an exemplary embodiment of the invention. In some embodiments of the invention, server 110 contacts (310) the mobile telephone company's voice mail server 120, in order to retrieve any available messages for user 140. Optionally, server 110 contacts a mobile telephone company using a mobile telephone line of the same company being contacted in order to minimize costs for retrieving messages. After connecting to the mobile telephone company, server 1 10 responds with tone selections to the voice options offered by voice mail server 120. As described above, in some methods server 110 responds by identifying the voice messages from a list, in some methods server 1 10 responds by identifying the pauses between the messages and in some methods server 110 responds by deciphering the message and/or by identifying tones or patterns, possibly simply the length of the voice mail notice. In an exemplary embodiment of the invention, server 110 is required to input (320) user 140's message password in order to validate server 110's authorization to access the stored messages. Optionally, the user password is stored in a database on server 110 together with the rest of user 140's details as described above. After supplying the user password, server 110 begins the process of selecting to play the next stored message (330), recording the message as it is played out by the voice mail server (340) and, optionally, for example depending on user setting, erasing the message from voice mail server 120 (350) after storing them on server 110. If there are more messages (360) stored for user 140 on voice mail server (120), server 1 10 repeats the above process from act 330 until act 350. Otherwise, if there are not any more stored messages, server 110 disconnects the connection (370). In some embodiments of the invention, the retrieved messages are encoded and stored in different formats (e.g. WAV, MP3) as selected by user 140 and/or according to the ability of the mobile telephone of user 140. In some embodiments of the invention, the quality of the message recording is user selectable. Optionally, a higher quality recording (e.g. using a higher sampling rate) results in a larger file and is optionally more expensive for user 140 since it consumes more system resources and takes more time to handle. In some embodiments of the invention, the messages are translated to text messages such as described in US patent 5,943,398 to Klein et al. and incorporated above in the background section of the application. Optionally, user 140 is required to pay an additional fee for message translation, however the total cost may be reduced for example due to transmission costs since text files tend to be much smaller than voice recording files. In some embodiments of the invention, only part of the message is encoded and/or translated and transmitted to user 140 for example depending on options selected by user 140. As shown in Fig. 2, after server 110 records a user's messages (220) it can send them to the user 140 (230). Optionally when the user signs up, the user selects one or more methods whereby the messages will be delivered to the user. In an exemplary embodiment of the invention, the method of sending messages is chosen in the interest of reducing communication costs. For example a user traveling outside of the mobile telephone company's region might request that messages be transmitted directly to his or her mobile telephone, using SMS messages such as "ringtone" messages or as messages translated into text. Optionally, more advanced data messages are used, for example, i-mode messages, GPRS and MMS. For ringtone messages, a telephone that supports 40-poly and up may be desirable. Optionally, a user can register his actual telephone as supporting one or more of these features (telephones may be replaced when changing countries). Optionally, server 110 keeps track of the country in which the user is located so that a cheapest transfer method may be used. Optionally, services that are unavailable in a particular country (such as MMS) are avoided. Optionally, a user can use a WWW browser provided in the telephone to view/hear messages and/or control server 1 10. Optionally, server 110 may be accessed using an interactive data service such as provided by many cellular providers (e.g., as used for weather and sports data). Alternatively or additionally, messages are transmitted in the interest of user comfort. For example a local user might prefer to receive messages as sound files attached to Email messages on a computer station 150, thus freeing the user from the overhead of calling the mobile telephone company and selecting options. It should be noted that costs for roaming can be very high, and may be largely avoided by the use of some embodiments of the present invention. Optionally, server 110 is used in a same country. For example, this method allows the user to store messages and/or listen to messages for an unlimited number of times with out paying for extra communication time. Optionally, server 110 can send a user an SMS message notifying the user upon reception of messages so that the user will know to check his or her Email or in order for the user to notify server 110 what to do with the messages for example discard, send by Email, send by SMS. In some embodiments of the invention, system 100 serves as a voice mail server for users 140. For example server 1 10 sends user 140 an SMS voice message with a first part of each message in order to notify user 140 to communicate with server 110 by a preferred method, for example via SMS or Email and select the messages of interest. In some embodiments of the invention, with some voice mail servers 120, server 110 can retrieve and supply user 140 with an SMS message containing the telephone numbers of the callers that left the messages in order to allow user 140 to select messages or directly contact the callers. In some embodiments of the invention, the numbers are transmitted to user 140 as voice messages. Alternatively or additionally, the recorded telephone numbers are translated to text and sent to user 140 as a text message. Optionally, after sending a sample or indication of the messages, server 110 waits for user instructions by methods described above, before transmitting the recorded messages. In some embodiments of the invention, server 110 waits for a preset amount of time for user instructions and transmits all the messages if no response is received. Alternatively or additionally, server 110 stores the messages or discards the messages if no user response is received. In some embodiments of the invention, server 110 or user 140 may place a limitation on the number of messages that system 100 retrieves and/or sends to user 140 over a specific time duration (e.g. day, week), in order to protect the user from paying for spamming or for erroneous messages and/or in order to limit the cost to a maximum sum that the user is interested in paying. Optionally, if the charges exceed a pre-selected limit the user is notified, for example by SMS, in order to provide further instructions. Alternatively or additionally, server 1 10 may send a list of telephone numbers and/or length of messages, for example so a user can select a best method of transmission and/or which messages should be transmitted. In some embodiments of the invention, each message is sent as one SMS message. Alternatively, messages are grouped together in one or more SMS messages in order to minimize the number of SMS messages in order to reduce costs. This may be done, for example, by sending one SMS message comprising two or more voice messages. In some embodiments of the invention, server 1 10 supplies users 140, for example by Email, with additional messages comprising system information, for example a transaction log, billing information and/or statistical reports. In some embodiments of the invention, other methods of message delivery are used, for example, server 110 supplies the messages to an Internet accessible web site and allows users 140 to access and/or download their messages in addition or instead of receiving them by Email. Alternatively or additionally, the messages can be sent using instant messaging on the Internet (e.g. ICQ). Optionally, server 1 10 uses a call-back service to provide messages. In one example, a user can send a telephone number (e.g., using one of the messages described above), for example a pay-telephone and the system will call up that number at reduced rates and serve as a voice mail system. Optionally, server 1 10 identifies a caller ID and can detect when a particular user called up and is waiting for a response. Optionally, a local telephone number is provided (optionally by a competing telephone company), to which a user can place a call at low cost. It should be noted that the above description referred mainly to retrieving messages from a mobile telephone company and transmitting them by other methods, however the above methods can be utilized for retrieving messages from any voice mail system in order to be transmitted to a user 140 by other methods as preferred by user 140. Optionally, server 110 is a personal program, for example which executes on a user's computer or on a cellular telephone .that optionally remains in the service coverage of the telephone provider (e.g., a JAVA application). The present invention has been described using non-limiting detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. It should be understood that features described with respect to one embodiment may be used with other embodiments and that not all embodiments of the invention have all of the features shown in a particular figure or described with respect to one of the embodiments. Variations of embodiments described will occur to persons of the art. Some embodiments are described as methods and include apparatus for carrying out the method, and vice versa. Also, computer readable media including software or instructions suitable for carrying out embodiments of the invention and/or logic steps thereof (e.g., when read by suitable hardware), are also within the scope of the invention. It is noted that some of the above described embodiments may describe the best mode contemplated by the inventors and therefore include structure, acts or details of structures and acts that may not be essential to the invention and which are described as examples. Structure and acts described herein are replaceable by equivalents which perform the same function, even if the structure or acts are different, as known in the art. For example, the term computer is meant to encompass various hardware, firmware, circuitry and/or software, in a single or multiple housings. Therefore, the scope of the invention is limited only by the elements and limitations as used in the claims. When used in the following claims, the terms "comprise", "include", "have" and their conjugates mean "including but not limited to".