See if you have Kppp loaded on your system. A simple search for kppp should find it if you have it loaded. If you don't have it on your system go to:
http://rpm.pbone.net/index.php3
and download kdenetwork*.rpm using the correct arch for your system.
You can view the KDE's Kppp HOWTo on the following web site:
http://linuxheadquarters.com/howto/...king/kppp.shtml
Kppp will let you query your modem to see that its working and by selecting parameters you will find the setup needed to make your modem work.
kdenetwork is also available using synaptic package manager from sources as Dag Wier's or KDE