Dial on Demand & Fetchmail

[Popcorn]

I have 2 problems I'm facing:

I'm running RedHat 8.0 + HiSax (Type=35) Modem.

Firstly I've setup my isdn modem and I can connect with:
isdnup ippp0
and I can disconnect with
ifdown ippp0
and all works well.

but, if I use ifup ippp0
and then do a ifconfig, I don't have an ipaddress assigned to my ippp0
interface.

I hope that isn't a problem that could be effecting my dial on demand.
how do I setup dial and demand to work...? I've set the dialmode to
auto and it seems to be online all the time. ???

second question is... what script is run when a connection is
established as I'd like to do a 'fetchmail'

-Popcorn