No subject

"  The branch parameter value MUST be unique across space and time for
   all requests sent by the UA.  The exceptions to this rule are CANCEL
   and ACK for non-2xx responses.  As discussed below, a CANCEL request
   will have the same value of the branch parameter as the request it
   cancels.  As discussed in Section 17.1.1.3, an ACK for a non-2xx
   response will also have the same branch ID as the INVITE whose
   response it acknowledges."

The ACK does not need to have the same branch as the INVITE if the
response was a 2xx final response. If your IP phone rejects the ACK because
the branch is different, it is the one that is not following the spec, not
Asterisk. 

Issue History 
Date Modified    Username       Field                    Change               
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2008-09-09 16:05 putnopvut      Note Added: 0092280                          
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