When the same INVITE message is received several times by the sip stack, it begins sending "482 Loop detected" every second forever.
It's not so easy to reproduce it. I've patched the standard simplecallsetup shootist in "trunk\src\examples\simplecallsetup" (see attached file).
After the first connection has been established and terminated via BYE, my code begins after 4 seconds to resend the same INVITE message without transaction every seconds 30 times.
The shootme will detect this replayed message and calls DialogFilter.sendLoopDetectedResponse(). From now on it sends the "482" message every second.
When receiving the first shootist log line "[java] Response received : Status Code = 482 CSeq: 1 INVITE" you can stop shootist.
After having stopped shootist I've left shootme running for 3 minutes, then stopped it and took a look in the shootmedebug.txt.
You'll see the following lines more that hundred times:
DEBUG - gov.nist.javax.sip.stack.SIPServerTransaction.fireRetransmissionTimer(SIPServerTransaction.java:1169) [fireRetransmissionTimer() -- gov.nist.javax.sip.stack.SIPServerTransaction@bc655bf8 state Completed Transaction]
DEBUG - gov.nist.javax.sip.stack.SIPServerTransaction.resendLastResponseAsBytes(SIPServerTransaction.java:1212) [resend last response SIP/2.0 482 Loop detected
The repetition will never stop.