asterisk users - Apr 2006 - How to route all incoming calls on an analog trunk to a specific ring group

I have a customer that is using a digium tdm2400p card with multiple analog
lines coming in. They want to be able to forward all calls on specific trunks to
specific ring groups. I tried this with the inbound routing and specifying the
phone number of the trunk and directing it to a ring group but this doesn't
work. Maybe I'm going about this all wrong. Any assistance would be
appreciated. Also callerid isn't showing up. i've checked all the
settings and callerid is set in the configs.

Tony