Hmmm, interesting. I was poking through my logs, and I see a flurry of registration failures up until 10:32 or so, when I switched to sip. I switched back and now it's okay. The suggestion to check via telnet to port 5060 is not really reliable, since that's going to use TCP, and not UDP. Sure it proves jupiter is up and reachable, but says nothing about whether it is not accepting SIP registration requests from me or not.
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