Incoming SIP provisional responses with SDP marked as retransmitted

[gfigiel]

There is an issue in Jain SIP RI that causes SIP11 RA does not deliver events to JSLEE application when provisional response (100 -200) is repeated with new content or header. The response is marked as retransmitted what prevents SIP11 RA from delivering the event towards SBB.

The issue is caused by comparing only response code (toString output) when checking response
retransmission:

jain-sip/src/gov/nist/javax/sip/stack/SIPClientTransactionImpl.java

Line 1548 in b79cba1

if (lastResponse != null && !sipResponse.toString().equals(lastResponse.toString())) {

A piece of the log message for the second 183 - with SDP

2017-06-09 21:13:23,353 INFO  [sip-UDPMessageChannelThread-5] [javax.slee.RAEntityNotification[entity=sip].SipResourceAdaptor] Dropping in dialog retransmission. Response:
SIP/2.0 183 Session Progress
Call-ID: 8655ee5d118fb53a61ec4315526c8f5d@10.96.48.40
CSeq: 1 INVITE
Allow: INVITE,ACK,OPTIONS,BYE,CANCEL,PRACK,UPDATE
Content-Type: application/sdp
Contact: <sip:10.203.8.188:5060;transport=UDP>
Content-Length: 265

[gfigiel]

Please assign me to this issue. I will make a PR in a while.