Try filling out contact-host too.  But if the far end gets pissed about your contact they are broken.

/b

On Sep 4, 2009, at 2:22 PM, Dmitry Bely wrote:

Well, you are right. Looks like the problem is not with authorization
but in the line

 Contact: <sip:gw+1.2.3.4@5.6.7.8:5080;transport=udp>

that the gateway would like to see as

 Contact: <sip:username@1.2.3.4>

I've found (almost undocumented) parameter extension-in-contact, but
it still gives

 Contact: <sip:username@5.6.7.8:5080;transport=udp>