GPRS and PPPD

Dear All!
Does someone manage to setup a GPRS connection using pppd?
The matter of the question is that i already tryed almost all available 
options, but always get the same return from the pppd:

pppd[1985]: Serial connection established.
pppd[1985]: Using interface ppp0
pppd[1985]: Connect: ppp0 <--> /dev/ucom0
pppd[1985]: sent [LCP ConfReq id=0x1 <auth pap> <magic 0xd1287498>]
last message repeated 4 times
pppd[1985]: LCP: timeout sending Config-Requests
pppd[1985]: Connection terminated, connected for 1 minutes

All chat scripts are working (as a result of chat script i can see ppp-specific characters to appear)
But whatever options i pass to pppd - the result is the same.

-- 
Best regads,
Anton Nikiforov