Using asterisk and siproxd together

Hi out there,

I’m currently trying to configure asterisk for use with siproxd.
Both are running on different machines. The siproxd is running
on my NAT firewall. In the curr. config I made a port redirection
(PREROUTING) of port 5060 to the firewall itself, because asterisk
is not able to specify an outboundproxy.

In the latest version of ast this is possible, and it works for outgoing
calls. I made an entry outboundproxy=“ip_of_siproxd” in a user
section in sip.conf, and this works fine for outgoing calls.
But unfortunately a similar entry in the global section does not work.
This behaviour results in an error msg. from my SIP provider
like this: …don’t use private ip address to register…

How can I configure ast to send register messages via my siproxd?