Is your TCP support "strange" in anyway? To clarify, the only softphone I can install on my android phone that works over TCP is sipdroid. None of the others work correctly over TCP. UDP is fine.
I've found the following posts on csipsimple issues forum which imply you aren't doing it correctly...
"pbxes.org has an weird bug with their server so that their support of TCP transport is not compliant with SIP specifications. SipDroid is not affected by the bug cause it does not follow the SIP specifications at the letter. " issue 604
"Again and again... that's cause pbxes.org DOES NOT SUPPORT true SIP (according RFC) over TCP !!!! SO DO NOT USE PBXES.ORG WITH TCP !!! DO NOT !
I'll notify on this thread if I found a workaround that change the RFC (rfc are standards) SIP behavior to work with the weird way pbxes.org manage TCP !!! But meanwhile DON'T use TCP with pbxes.org. You can also cry to pbxes.org cause their server is not compliant with rfc regarding TCP..."
issue 705
If it is an issue with you, is it likely to be fixed?
