Q24PLUS network connection problems


I am able to establish a PPP connection from a Linux box (running RHEL 4.0) to the Wavecom Q24Plus module, but the PPP connection seems almost useless to me. I am not able to ping well-known public IP addresses, such as (yahoo), or do anything else through it.

I am using the Wavecom Q24Plus module with a SIM card from Rogers (Canada) that works correctly on our Sony-Ericsson Edge card.

Can someone point me to a trouble-shooting guide for the Q24Plus that would assist me in isolating the problem?

Thanks very much.