CM 5.04 - new to sip phones
Lab environment and very basic configs such as using none partition and none CSS and no calls across wan.
Both SIP and SCCP phone is registered to same CM and on same subnet. Call is establish but no rtp stream.
Both phones are able to call out to H323 GW
Currently the sccp phone is using G729
Did you configure any acess-list ,check if it is blocking the the rtp streams across the wan link
amercado is reporting no rtp stream between phones on the same subnet, not crossing a router, hence cannot be an ACL issue.