Here's how I have solved that problem (guerilla figha helped me a lot whith his post):
1. Uninstall kppp (it's in some network package i think kdenetwork or something like that)
2. Delete all things in /etc/ppp directory
3. Install kppp
4. make /etc/ppp/peers directoru
5. touch kppp (create file kppp)
6. edit kppp and add a line plugin passwordfd.so
7. copy /etc/ppp/peers/kppp to /etc/ppp/options (options is a file)
After that everything works just fine.
When I'm using kppp as a root
When I'm in user mode (I've done the chmod), I get connected with ISP, but I cannot get anything from the net (opera and ksirc: unnable to locate network or something like that)
Why I't haave to be so hard???