It's almost two years and I've had to reconstruct my OS a few times since the original posting and thought to add the following to the information I learned along the way to solving the modem problem in installing Mepis 6.0. A friend of my in Denver gave me an article on using the "minicom" command line in a root terminal window to discover where the internal modem is installed on your system. I recently revisited the link and found it very helpful in quickly getting the information about the modem.
Hope this will help someone along their way:
http://www.linuxjournal.com/article/5448
Good luck and best wishes,
Maillo