newbie using PPP

Im trying to conect my notebook to the net (a dial up) with FBSD4.8 using PPP.
Ive set the device card0 seeing that Im using pccard modem. When I open the term it opens and flips back to PPP.
Is this cause the card is not compatible?
Or am I not configuring the device corectly?
I havent touched pppd configuration as Ive understood this is not nescesary if using ppp this way?
Has anyone got path to a tutorial about devfs naming.
thanks