We have witnessed a minor issue with Polycom Soundpoint 501s where they may reject being transferred when calling from line 2 or 3. The most recent application version we have seen this on is the 2.1.2.0078 release. The scenario is as follows, a Polycom Soundpoint is configured to register to 2 SIP addresses each in a different domain. For example phone X registers with addresses:
When a call is placed on line 2 from email@example.com the call seems to proceed as normal, until the remote end sends a SIP REFER, at which point the Soundpoint will send back a SIP 481 message, "Call Leg/Transaction Does Not Exist". This bug prevents transfers from working properly from calls placed on line 2 of this phone.
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