ShadowWalkeR - 2012-04-04

Hi, sorry for my english - im from russia.
I try realise next scheme: OpenSIPS contain all sip registers. If one sip user call to another sip user, call should go thru asterisk. Asterisk work as mediaproxy, but without nat.
I just start learn opensips, so i don't understand how it fully realise.
Can someone help me with this task?