Here the details:
U 2010/02/05 09:06:32.497347 10.100.0.101:5062 -> 10.0.255.10:5061
INVITE sip:12345@10.0.255.10:5061 SIP/2.0.
Contact: <sip:45400@10.100.0.101:5062>.
U 2010/02/05 09:06:32.521248 10.0.255.10:5061 -> 10.100.0.106:5065
INVITE sip:12345@10.100.0.106:5065 SIP/2.0.
Contact: <sip:45400@10.0.255.10:5060>.
Actually I do not see in your config that the Contact is rewritten.
Either there is something strange with your config, or maybe there is a
SIP ALG somewhere inbetween which mangels the contact headers.
regards
klaus
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