Please Help Port Forwarding Issues regarding - Router - Wireless Router & Voip

hey guys i recently just had one Cable Modem (ADSL) then recently just hooked up my Wirless Router to it and now my father has installed VOIP...

Before all of that i had port forwarding wokring just fine on the one modem and now i cant seem to connect to emule what so ever..

This is how it is wired

Cable Modem (ADSL) from that it goes into the Wireless Router & then the voip box is connected to one of the outletts in the wirless router


Is it possible to run portforwading at all ? any help or ideas would be great..

cheers

pete