Abstract:
The invention is directed towards an automated system for extracting voice messages from a voice mail system and for providing unified access to voice mail and electronic mail or voice mail and the internet. For a given user, a voice mail remote access server connects to the user&#39;s voice mail system through a telephone or data network, and uses speech recognition and understanding to navigate through the prompts of the voice mail system and extract the user&#39;s voice mail. Depending upon the access mechanism preferred by the user, the voice messages are sent as e-mail messages with attachments (audio files) to the user or made accessible to the user&#39;s world wide web server or displayed to the user using a stand-alone voice mail player application.

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to methods of accessing voice mail over telephone or data networks and, more particularly, to a system and a method for accessing voice mail from a remote voice mail server using electronic mail or a web browser or a dedicated voice mail client. 
     BACKGROUND OF THE INVENTION 
     DESCRIPTION OF THE PRIOR ART 
     FIGS. 1A and 1B show examples of voice mail systems  50 . Voice mail systems  50  enable users to record, manage, retrieve and send spoken voice messages to and from other users. Thus, examples of voice mail systems include both a telephone answering machine and an automated telephone based spoken messaging system for a large corporation. An interactive voice response system which provides spoken voice information to the user over a telephone can also be considered to be a voice mail system. For example, an automated telephone banking system which provides account balances over the telephone can be considered to be a voice mail system. 
     The telephone is the most common means of accessing and recording voice mail (e.g., the IBM voice mail system). However, some voice mail servers (e.g., the new release of lotus notes) may additionally provide access to voice mail lover a computer data network (e.g., over the internet or an intranet), where the users can give voice mail commands using the keyboard and mouse. FIG. 1A shows a user accessing her voice mail over the telephone and FIG. 1B shows a user accessing his voice mail through the computer. 
     FIG. 1C shows a typical mail access session  40  of a user with a voice mail system  50  over the telephone. After a user calls her voice mail system, the user authentication  20  is performed by the user entering her name and her password using the dual-tone multi frequency (DTMF) keys on her telephone when prompted to do so by the voice mail system  50 . The voice mail system  50  then provides the user with an option of choosing one of a possible set of actions by pressing DTMF keys on the telephone. Dual-tone multi frequency keys (DTMF) are a form of address signaling provided on telephone sets using push-buttons instead of a rotary dial. For instance, in our example, a choice of recording a voice message is indicated by pressing “1” and a choice of listening to the user&#39;s voice mail messages is indicated by pressing “3”. The directions provided by the voice mail system  50  to the user to navigate through the menu are called voice prompts  30 . The user understands the prompts and presses the appropriate DTMF keys to access her voice mail messages  10 . FIG. 1C also shows an example of a voice mail message  10  and the process of navigating the voice prompts  30  to extract the message. Thus, the process of extracting the voice mail messages  10  in a mail access session  40  involves a navigation through the voice prompts  30  of the voice mail system  50  until the voice messages  10  are played back. 
     Some voice mail systems may also provide access to voice mail over a data network (e.g., a TCP/IP connection over the internet). In this method of access, a client computer interacts with the voice mail system using a set of messages in an agreed upon protocol (e.g., TCP/IP) and sends or receives the voice mail as compressed audio files. 
     The main problem with traditional mail systems is a lack of integration among the different types of messaging that a user access. Thus, a typical business user is forced to use the telephone to access her voice mail, an electronic mail client program on her computer to access her e-mail and a world wide web browser on her computer to access the world wide web. 
     Another problem is the lack of an automated method to navigate the voice prompts  30  of a traditional voice mail system  50  to extract voice mail messages. Thus, the users are either forced to switch to a more sophisticated voice mail system or to navigate through the prompts manually. 
     OBJECTS OF THE INVENTION 
     It is therefore an object of the present invention to provide a system and a method for enabling access to voice mail synchronously or asynchronously from a remote voice mail server through an electronic mail client or a network browser (e.g., a world wide web browser) or a stand alone voice mail client. 
     It is yet another object of the present invention to provide a system and a method for automatically extracting voice mail messages from a voice mail server using speech recognition and natural language processing technologies by navigating through the voice prompts, for presentation to a user at a later time. 
     SUMMARY OF THE INVENTION 
     The invention is directed towards an automated system for extracting voice messages from a voice mail system and for providing unified access to voice mail and electronic mail or voice mail and the internet. For a given user, a voice mail remote access server connects to the user&#39;s voice mail system through a telephone or data network, and uses speech recognition and understanding to navigate through the prompts of the voice mail system and extract the user&#39;s voice mail. Depending upon the access mechanism preferred by the user, the voice messages are sent as e-mail messages with attachments (audio files) to the user or made accessible to the user&#39;s world wide web server or displayed to the user using a stand-alone voice mail player application. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other objects, aspects and advantages will be better understood from the following detailed description of a preferred embodiment of the invention with reference to the drawings, in which: 
     FIG. 1A is a schematic diagram showing a human user accessing her voice mail messages from a prior art voice mail server using a telephone over a telephone network. 
     FIG. 1B is a schematic diagram showing a human user accessing his voice mail messages from a voice mail server using a prior art computer system over a data network. 
     FIG. 1C is a sample mail access session by a user with a prior art voice mail system showing voice prompts played by the voice mail system and the navigation performed by the user. 
     FIG. 2A is a block diagram showing a generalized voice mail access scenario using our invention, where client computers are interacting with a voice mail remote access server (VMRAS) to access voice mail from a voice mail system. 
     FIG. 2B shows the user interface provided by network browsers with a voice mail player plug-in to enable users to access their voice mail from the world wide web. 
     FIG. 2C shows the user interface provided by e-mail clients with a voice mail player add-on to enable users to access their voice mail messages as e-mail messages with attachments. 
     FIG. 2D shows the user interface provided by a voice mail player application to enable users to access their voice mail messages. 
     FIG. 3 is a block diagram of the basic components of a voice mail remote access server (VMRAS). 
     FIG. 4 is a block diagram of a voice control packet used by client computers to communicate voice mail commands to the VMRAS. 
     FIG. 5 is a block diagram of a voice data packet used by the VMRAS to communicate voice mail messages to the client computers. 
     FIG. 6 is a block diagram of an audio packet used by the voice mail system to send voice mail messages to the VMRAS. 
     FIG. 7 is a block diagram of a signal packet used by the VMRAS to send voice mail commands and voice mail messages to the voice mail system. 
     FIG. 8 is a block diagram of a user&#39;s registry within the VMRAS. 
     FIG. 9 is a block diagram of a session manager within the VMRAS. 
     FIG. 10 is a block diagram of a message parser within the VMRAS. 
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings and more particularly to FIG. 2A, there is shown a block diagram of the overall system  250  architecture. Client  1 , Client  2  and Client  3  are typical personal computers equipped with a sound card and a network interface, e.g. an IBM Aptiva personal computer or a Packard Bell personal computer. The data network interface  291  is a network card, such as token ring, or a modem for dial-up type connections. The voice messaging interface  292  is a network interface capable of communicating voice mail system commands to the voice mail server. Examples of a voice messaging interface  292  include a telephony network, a digital network connected to a telephony server, a digital internet protocol (IP) network connected to a telephony server, a dedicated RS-232 connection to a telephony server, or a synchronous or asynchronous data communication network connected to a telephony server. All of the data network interfaces and the voice messaging interfaces mentioned above are well known. The users of the computers Client  1 , Client  2 , and Client  3  access their voice mail through a world wide web browser  221  with a voice mail player plug-in  801  (FIG.  2 B), an electronic mail client program  222  with a voice mail player add-in  802  (FIG.  2 C), and a separate stand alone voice mail player application  803  (FIG.  2 D), respectively. The web browser  221  on Client  1  is connected to the web server  251  over the internet or an intranet. The e-mail client  222  is connected to the e-mail server  252  over the internet or intranet. The Netscape navigator and the Microsoft Internet Explorer are examples of a world wide web browser  221 . The Lotus notes client program is an example of an electronic mail client program  222 . The web server  251 , the e-mail server  252 , and the voice mail player application  803  are connected to the Voice Mail Remote Access Server (VMRAS)  200  with data links  101 (A,B, and C) respectively. For example,  101 A, B, and C can be internet connections or Local Area Network (LAN) connections. 
     The Voice Mail Remote Access Server (VMRAS)  200  module: 
     establishes a connection  102  to a voice mail system  50  over the voice messaging interface  292  (a telephone or data network), 
     extracts digitized voice messages  10  from the voice mail system  50 , which are received either as an audio stream (if the connection is over the telephone network) or as audio packets  203  (if the connection is over a data network), over the data link  102 , 
     sends the digitized voice messages to the client computers Client  1  (through a web server  251 ), Client  2  (through an e-mail server  252 ) and/or Client  3  over the data links  101 A,  101 B, and  101 C using voice data packets  204 , 
     receives voice control commands ( 901 / 201 ) (to control the voice mail system  50 ) or input voice messages ( 904 / 201 ) to send to others (see FIG. 4) from the client computers Client  1  (through a web server  251 ), Client  2  (through an e-mail server  252 ), and Client  3 , sent as voice control packets  201  over the data links  101 A, B and C, and 
     sends the voice mail commands  901  or the input voice messages  904  (see FIG. 4) to the voice mail system  50  either as a set of appropriate dual-tone multi frequency (DTMF) keys (if the connection is over the telephone network) or using signal packets  202  (if the connection is over a data network) over the data link  102 . 
     The VMRAS  200  is connected to the voice mail system  50  via a known Computer Telephony Interface (CTI) or a data network interface. This connection, represented as  102  in FIG. 2, is preferably over the telephone network. 
     The computers Client  1 , Client  2 , and Client  3  send voice control packets  201  containing voice mail commands  901  to access and control their voice mail, to the voice mail remote access server  200  over the respective data links  101 A,  101 B, and  101 C. The client computers receive voice data packets  204  containing voice mail messages  10  over the data links  101 A,  101 B, and  101 C respectively from the voice mail remote access server  200 . 
     The user on Client  1  uses a web server  251  to connect and authenticate herself to the VMRAS  200  and receives her voice mail messages  10  as an audio stream. FIG. 2B shows an embodiment of the user interface of the web page shown to the user by her web browser  221  to enable access to her voice mail. The voice mail player plug-in  801  (FIG. 2B) in the web browser  221  implements a playback function  261  for playing the audio stream, e.g., voice message ( 10 ,  262 ) in real-time as it is being received from the VMRAS  200  and a front-end user interface that allows the client to interact with the voice mail system  50  as if she were using a regular telephone. In one preferred embodiment, a description  263  of the message ( 10 , 262 ) is shown. 
     FIG. 2C shows the user interface provided by the voice mail player add-in  802  in a e-mail client  222  which enables the user on Client  2  to use her electronic mail client  222  to retrieve her voice mail asynchronously from the e-mail server  252 . In this case, the VMRAS  200  sends the voice mail messages  10  as standard e-mail attachments (audio files) to the user&#39;s mailbox. For example, an embodiment of VMRAS  200  might send the messages  10  as attachments which are wav files or real audio files using standard messaging protocols like SMTP. The voice mail player add-in  802  allows the e-mail client  222  to novelly playback  266  her voice mail messages  10  using the speakers on her computer Client  2 . As before, the message can have a descriptor  263 . 
     FIG. 2D shows the user interface of a voice mail player application  803  on Client  3  which enables a user to access her voice mail. The voice mail player  803  optionally authenticates the user to the VMRAS  200  by providing her user name  271  and password ( 272 , see also  20  in FIG.  1 C). The user interface of the voice mail player  803  (FIG. 2D) allows a user to retrieve (button  273 ) her voice messages  10  and play them back or to record (button  275 ) and send messages  904  (see FIG. 4) to other users. The voice mail player application  803  could be a Java application that provides similar functions to those described for the Voice Mail Player Plug-in  801 . A specific identifier  274  can be provided to the system  250  to enable the system  250  to access any given voice mail system  50 . This identifier  274  can be a telephone number or an IP address of a network server. 
     FIG. 3 shows a block diagram of the basic components of a Voice Mail Remote Access Server (VMRAS)  200 . The users registry  300  within VMRAS is a database of users  410 A and their associated voice mail locations  420 A (see FIG.  8 ). The session manager  400  manages the connections  101 A,B,C, with the web server  251 , the e-mail server  252  and the client computer Client  3 . The connections can be of 2 types: synchronous or asynchronous. A synchronous connection allows users on client computers to listen to their voice mail messages  10  in real-time. An asynchronous connection allows users on client computers to receive their voice mail messages as e-mail attachments. The session manager  400  accesses a user&#39;s voice mail locations ( 420 A or  420 B) from the users registry  300  (FIG.  8 ), establishes a connection  102  (FIG. 2A) to the voice mail system  50  using either a voice mail direct access API  230  over a voice messaging interface  492 : a data network or a computer telephony interface (CTI)  220  over the telephone network. The voice mail direct access API  230  is based on the voice mail network interface API or the voice mail network operating system API and implements known functions such as: get next voice message, delete voice message,etc. (One example of a voice mail direct access API  230  is IBM&#39;s “Direct Talk Mail System” within the DT 6000 telephony product.) The computer telephony interface (CTI)  220  is a hardware or software component that can dial into the voice mail system  50  and send it DTMF tones. The CTI unit  220  uses a known codec  210  to compress digitized voice, if necessary. After establishing a connection  102  between the voice mail system  50  and the VMRAS  200 , the session manager  400  performs user authentication  20  (FIG.  1 C), navigates through the voice prompts  30  of the voice mail system  50 , and extracts the voice mail messages  10  using the message parser  500 . The message parser  500  uses well known speech recognition and natural language processing technologies to recognize the prompts and extract the voice mail messages  10  from the audio stream. 
     The client computers (Client  1  through the web server  251 , Client  2  through the e-mail server  252 , and Client  3  directly) send voice control commands  901  (FIG. 4) for interaction with the voice mail system  50  in the form of voice control packets  201  to the VMRAS  200 . In return, the VMRAS  200  sends voice messages  10  in the form of voice data packets  204  to the client computers (Client  1  through the web server  251  and Client  2  through the e-mail server  252 ). If the connection  102  (see FIG. 2A) is over a data network, the VMRAS sends commands to the voice mail system  50  in the form of signal packets  202  and in return obtains voice messages in the form of audio packets  203  from the voice mail system  50 . If the connection  102  (see FIG. 2A) is over the telephone network, the VMRAS  200  sends commands to the voice mail system  50  in the form of DTMF signals and in return obtains voice messages  10  as an audio stream over the telephone. 
     FIG. 4 shows the specification of a voice control packet  201  used by the client computers to send commands to the VMRAS  200  over the data network interface  291 . For example, record messages  275  (in FIG. 2D) is sent as an input voice message  904  within the voice control packet  201 . A voice control packet consists of a voice control command  901  comprising a control packet identification number  902  followed by a variable length command string  903  and/or an input voice message  904  comprising of a control packet identification number  902  followed by a variable length digital voice recording  905  or a text message. The control packet identification number  902  is typically a long integer used to uniquely identify a voice control command  901  or an input voice message  904  but can be any other type of identifier. This number  902  can be used to encode the packets for the communication protocol being used (e.g., TCP/IP, UDP, etc.). Possible values of the command string  903  are voice mail system commands, user commands or selections for the voice mail system and/or user profiles. Examples of voice control commands  903  are: “connect”, “disconnect”, “go to next”, “go to previous”, “receive all messages”, etc. The digital recording  905  is typically a variable length compressed or uncompressed audio file using known techniques. 
     FIG. 5 shows the specification of a voice data packet  204  used by the VMRAS to communicate voice messages (over the data network interface  291 ) to client computers where the users access voice mail using the stand alone voice mail player  803  (FIG.  2 D). The information provided in the interface  803 , (e.g.,  271 - 275 ) is communicated in the packet  204 . For example the retrieved messages  273  would be communicated in block  905 . A voice data packet  204  comprises a voice message header  906 A with a data packet identification number  907  and a variable length string  908  followed by an output voice message  906 B having a data packet identification number  907  followed by a variable length digital recording  905  or a variable length text message  909 . The data packet identification number  907  is typically a long integer (or any other identifier) used to uniquely identify a voice message header  906 A or an output voice message  906 B. The variable length string  908  contains information about the voice mail messages. Examples of the variable length string  908  include an e-mail header, a message timestamp, a message caller-id (using well known technology), the position of a particular message in a queue of messages, a list of messages for selection by the user, etc. The digital recording  905  is typically a compressed or uncompressed audio file and the message text  909  is a textual transcription of the voice mail message (if the voice mail system supports it). 
     For client computers where users are accessing their voice mail through their web browser  221 , the voice data packets  204  are in the hyper text markup language (HTML) with embedded audio files (e.g., in wav or realaudio format). For client computers where users are accessing their voice mail through e-mail, the voice data packets  204  are in the standard SMTP or other mail format with the audio files being sent as attachments. Both the HTML and SMTP are well known. 
     FIG. 6 shows the format of audio packets  203  used by the voice mail system  50  to communicate with the VMRAS  200  over the voice messaging interface  292 . If the connection  102  between the VMRAS  200  and the voice mail system  50  (see FIG. 2A) and the voice messaging interface  492  is over a data network using a direct access API or a data network (e.g., using TCP/IP over a computer network or internet), the audio headers include information related to the communications protocol being used. Otherwise, the whole audio packet  203  is an audio stream over the telephone. An audio packet consists of a sequence of audio headers  910  followed by audio messages  911 . The audio headers  910  contain voice prompts  30  played by the voice mail system (see FIG. 1C) or file descriptors for audio files containing voice recordings or structural information (e.g., file type, file length etc.) about audio files containing voice recordings. The input audio messages  911  are the voice messages played by the voice mail system  50 . Examples of audio messages  911  include audio files containing voice recordings in compressed or uncompressed form. 
     FIG. 7 shows the format of a signal packet  202  used by the VMRAS to communicate voice mail commands to the voice mail system  50  over the voice messaging interface  292 . If the connection  102  between the VMRAS  200  and the voice mail system  50  (see FIG. 2A) is over a voice messaging interface  292  using a direct access API (e.g., using TCP/IP over the internet), the audio control signals  912  include information about the communications protocol being used, and the output audio messages  913  are digitized audio files (e.g., in wav or realaudio format) containing the voice mail messages  10  recorded by users for others. If the voice messaging interface  292  is a telephone network, the whole signal packet  202  comprises dual-tone multi frequency (DTMF) tones and audio recordings representing voice mail commands or telephony server file management commands. If the voice messaging interface  492  is a digital data network, a signal packet  202  comprises a sequence of audio control signals  912  and output audio messages  913  in the order shown in FIG.  7 . The audio control signals include commands to the voice mail system to navigate through the voice prompts  30  (FIG.  1 C), i.e. DTMF tones. The output voice messages  913  typically are audio streams containing the voice messages recorded by users. Examples of an output voice message  913  include a text e-mail message, an audio attachment to an e-mail message, a pager command, a compressed or uncompressed audio stream. 
     FIG. 8 is a block diagram describing the general layout of the users registry  300  within the VMRAS. Some of the embodiments could be organized as a flat file or as a database such that there is one record for each user  450 A or company  450 B. A company in this case is defined as a group of one or more users with a common set of voice mail locations. 
     The single user record  450 A comprises the user identification  410 A (such as her name), one or more voice mail locations and phone numbers  420 A, and an optional entry specifying the phone mail locations templates  430 A. The templates define the menus and selection options that the user has when listening to her voice mail messages. 
     The company record  450 B comprises the company&#39;s name, and a list of its employees  410 B that are authorized to use the voice mail system, along with a list of voice mail locations  420 B and, optionally, a list of location templates  430 C. 
     FIG. 9 is a block diagram of the session manager  400  within a VMRAS  200 . When a user tries to access her voice mail using her web browser (FIG. 2B) or a stand alone voice mail player application  803  (FIG.  2 D), the client computer (Client  1  or Client  3 ) sends a voice control packet  201  to the VMRAS  200  asking it to open a voice mail session  40  (see FIG.  1 C). The user session control unit  452  within the session manager  400  receives the voice control packet  201 . The user session control unit  452  accesses the user&#39;s authentication information  410 A (e.g., the user name and password as shown in FIG. 1C) and the location  420 A (phone number of IP address) of the user&#39;s voice mail server  50 , from the users registry  300 , authenticates the user (e.g., verifies the password) and activates the voice mail control module  451 . The voice mail control module  451  establishes communication  102  (see FIG. 2A) with the user&#39;s voice mail system  50  either over the telephone network through the CTI  220  or using the voice mail direct access API  230 . If the communication  102  is over the telephone network, the CTI unit  220  calls the voice mail system  50 , and sends the audio response from the voice mail system to the message parser  500 . The message parser  500  extracts the voice mail messages  10  (the extraction process is explained in detail later, see FIG.  10 ), if any, of the user, and sends them as an audio stream to the audio stream playback control unit  450  in the session manager  400 . If the communication between the VMRAS  200  and voice mail system  50  is through the voice mail direct access API  230 , the voice messages  10  are directly sent from the voice mail server  50  to the voice mail control module  451 , which in turn sends the messages  10  to the audio stream playback control  450 . The audio stream playback control unit  450  formats the audio data of the voice messages using the codec  210  and sends voice data packets  204  (as HTML for web users) containing the extracted voice messages  10  to the web server  251  (for web users) or Client  3  (for users using a stand alone voice mail player application  803 ). The voice mail plug-in  801  on Client  1  or the voice mail player application  803  on Client  3  enable the user to access her voice mail (through her web browser  221  for Client  1 ) and listen to her voice messages  10  over the speakers of her computer. 
     If the user is accessing her voice mail through her e-mail, the e-mail agent  453  in the session manager  400  within VMRAS  200  periodically checks the user&#39;s voice mail from the voice mail system  50 . For example, every twenty minutes, the e-mail agent  453  (FIG. 9) looks up information ( 410  and  420 , see FIG. 8) about users using e-mail from the user&#39;s registry  300  through the user session control  452 . The user session control  452  activates the voice mail control module  451 , which uses either the voice mail direct access API  230  or the CTI  220  and the message parser  500  to extract voice messages  10 , as described above. 
     In this case, the extracted messages  10  are sent to the e-mail agent  453  which sends e-mail messages (e.g., using SMTP protocol) in the form of voice data packets  204  to the e-mail server. The voice mail player add-in  802  enables the e-mail client on Client  2  to playback the voice messages  10  through the speakers of her computer. 
     FIG. 10 shows a block diagram of a message parser  500 . The CTI unit  220  receives instructions from the voice mail control module  451  in the session manager  400  to extract a user&#39;s voice mail from a voice mail server  50 . The CTI sends all audio output from the voice mail system  50  to the speech recognition unit  550  within the message parser  500 . The speech recognition unit  550  uses well known speech recognition technology (e.g., using IBM Via Voice or the Dragon speech recognition system) to recognize the response from the voice mail system  50  as voice prompts  30 . The recognized voice prompts  30  (e.g., see FIG. 1C) are sent to the dialog management unit  551  by the speech recognition unit  550 . The dialog management unit  551  employs standard known natural language processing technology (e.g., see the text “Natural language processing, a knowledge engineering approach”, by Richard Cullingford, Rowman &amp; Littlefield 1986, which is herein incorporated by reference in it entirety) to understand the voice mail prompts  30 , and extract prompt strings from the audio stream played by the voice mail system  50 . Examples of a prompt string include a number denoting the position of a voice message in a stream of messages, a timestamp representing the time of recording of a message, a telephone number, an extension of a person or a person&#39;s name representing the caller-id (well known technology) etc. The dialog management unit  551  instructs the CTI unit  220  to generate DTMF keys as necessitated to navigate through the voice prompts  30  (e.g., as shown in FIG. 1C) until the voice mail messages  10  are played by the voice mail system  50 . For instance, upon initiation of a call with the voice mail system  50 , the dialog management unit  551  determines the exact timing in the conversation, when it is appropriate to play the user&#39;s name and password to the voice mail system for authentication  20  purposes (e.g., as shown in FIG.  1 C). This playback (interspersed appropriately with DTMF tones) is performed by the CTI unit  220  when instructed by the dialog management unit  551 . After user authentication  20  with the voice mail system  50 , the dialog management unit  551  analyzes the next prompt  30  (FIG. 1C) played by the voice mail system. If the prompt  30  is “you have no new messages”, the dialog management unit  551  understands it and asks the CTI unit  220  to terminate the call with the voice mail system  50 , after sending an appropriate e-mail message to the e-mail agent  453  or the audio stream from the voice mail system  50  depending upon the method of access. If the prompt  30  from the voice mail system  50  is “you have 7 new messages”, the dialog management unit  551  navigates through the prompts of the voice mail system  50  by instructing the CTI unit  220  to send appropriate DTMF tones, until the first message  10  (e.g., see FIG. 1C) is about to be played. The dialog management unit  551  then instructs the CTI  220  to record the audio stream of the voice mail system  50  by sending instructions to a message recorder  553 . The message recorder  553  records all the output of the voice mail system using known technology (e.g., the voice recording capability in CTI products like the IBM DirectTalk/6000 product), until instructed to stop by the dialog management unit  551  (through the CTI unit  220 ). The recorded voice mail messages  10  are sent to the dialog management unit  551 , which in turn sends them to the message formatter  552 . The message formatter  552  formats the voice mail messages  10  either 
     as an audio stream, or an HTML message (depending upon the users method of access), and sends it to the audio stream playback control  450  in the session manager  400 , or 
     as an e-mail message with an attachment and sends it to the e-mail agent  453  in the session manager  400 . 
     The above steps are repeated until all the voice messages of the user are extracted.