PM50232; 7.0.0.19: sip proxy is not re-using tcp/tls connections for outbound si

PM50232 resolves the following problem:

ERROR DESCRIPTION:
Previous to Fix Pack 15, the SIP Proxy used currently
existing inbound TCP/TLS connections for outbound SIP requests.
A regression occurred in Fix Pack 15 so that under some
scenarios, the SIP Proxy does not re-use the connection, but
instead attempts a new outbound connection. This attempt
sometimes fails because in certain environments, we hit TLS
certificate issues or firewall issues.

LOCAL FIX:
Rollback 7.0.0.15 appserver fixpack to previous working version

PROBLEM SUMMARY

USERS AFFECTED:
All users of the IBM WebSphere Application
Server Session Initiation Protocol (SIP)
Proxy

PROBLEM DESCRIPTION:
SIP Proxy does not re-use inbound
client TCP/TLS connections for
outbound requests.

RECOMMENDATION:
None

In some scenarios, the SIP Proxy will fail to re-use inbound
client TCP/TLS connections for outbound requests. In a
scenario where the client issues a SIP REGISTER on a client
connection, the SIP Proxy normally uses the same client
connection for outbound requests (based on the CONTACT headers
registered). This behavior changed starting in Fix Pack 15.
Currently, the SIP Proxy will attempt a new TCP/TLS connection
to the client. In some network environments, this may not be
possible, resulting in a dropped SIP request.

PROBLEM CONCLUSION:
Code has been correct to re-use the connection.
The fix for this APAR is currently targeted for inclusion in
fix pack 7.0.0.23 and 8.0.0.3. Please refer to the Recommended
Updates page for delivery information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980