asterisk users - Oct 2003 - Dial-out using Asterisk

I have to dial out to a customer site ... We now only have our E1 & 
Asterisk to call out.

I think I can set-up an ATA-186 and a regular analog modem to do it, but 
is it possible to use on of the 32 channels of the E1 as a 64kbit/s PPP 
ISDN dial-out line ? How ??

Thanks