[Asterisk-Users] Asterisk vs Sipura SIP problem?

[Luki]

Can't help you much here but I know for a fact that a SPA 3000 works
perfectly fine with Asterisk (I got one). It's also correct that
Asterisk will not show anything if an incoming INVITE does not match
anything. Try SIP DEBUG and see what exactly is happening, where
asterisk is looking for the extension, etc. You may also want to
enable debugging in asterisk (see debug option in logger.conf) and
increase the debug level (SET DEBUG 9) and verbosity (SET VERBOSE 9).
This info will tell you more why asterisk answered the way it did.

Looking for xyz in incoming (domain xyz.com)
list_route: hop: <sip:user at 1.2.3.4:5060>
Transmitting (NAT) to 1.2.3.4:5060:
SIP/2.0 100 Trying

etc...