For any Asterisk users out there using sipme as their Voice-over-IP provider who, like me, have been banging their heads against walls trying to figure out why it isn’t working, it turns out that sometime in early February, they made a change to their SIP proxy setup and elected not to mention it on their website.
Their new equipment apparently doesn’t like talking to Asterisk, so to make it work, it’s necessary to mask the user agent string by putting the following in the [general] section of your sip.conf file:
useragent=portasipfriendly
…which I found out only after considerably websearching let me stumble upon this thread in Whirlpool.
Evidentally, I haven’t made any non-Melbourne phone calls for almost two months, or I’d have discovered this earlier.