When the phone says temp fail it means that the RTP stream is still up but signaling is down. For example you wouldn't be able to place the call on hold but the conversation could continue.
We see this fairly often when the port names on a failover pair are the same. They should not be configured this way. Each set of ports needs its own unique name.
It could be this as well:
http://www.cisco.com/cgi-bin/Support/Bugtool/onebug.pl?bugid=CSCdz76351
Thanks,
Keith