MNP or Microcom Networking Protocol is a system, present on many of today's more modern modems, that adds error checking and data throughput enhancing compression to a telecommunications session. If your situation is " I called... got a CONNECT message and then nothing happened! " you've experienced the joy of a failed MNP handshake! The approved way to avoid future occurrences of this unseemly behavior, is to disable the MNP features of your modem.
In the wonderful world of standards we find the AT command set. This uniform code of modem jargon specifies a large number of ways to disable MNP. A common method is changing \\N1 to \\N0. You really need to consult the owners manual of the specific modem you are using to find out the correct one. To enter a custom setting, hold the option key while accessing the modem selector popup in the Settings/ Connection dialog. You should see the word 'custom' at the bottom of the list. Select this option and edit the command string to alter the setting of the MNP portion. The 1.0 modem tool that shipped with ClarisWorks will not allow you to save the custom setting but the 1.1 tool available from your dealer or APDA will allow you to save it.
Another approach is to use V.42b standard compression instead of MNP. This will give the same functionality but will have less connection bugs and will be a little faster.