Considering I know of a few in existence (although most I haven't even been able to find a vendor selling the program even) I'm sure something is available for what I need it to do. Main reason behind my need for it to support both wifi and cdma evdo standards is due to location. I generally get great evdo signal around here so when not on wifi it would work fine I think.
Hopefully someone will know of a useful app that can handle client side SIP and the like.
search google for SJphone , that will do what your looking for , my results have been pretty mixed , since when you speak it is sending data , and the capacity of the EVDO networks is a bit spotty on that end.
I ended up searching and digging around a bit ago, forgot to update this thread but yes I ended up finding SJphone and it does work fairly good. Granted it does get choppy at times due to the evdo uplink speed and/or latency.