Incoming anonymous calls being rejected - obvious settings already checked

[grd]

We have incoming anonymous calls being rejected on a MiVoice Business system (8.0 SP3). Looking at network traces anonymous calls appear as coming from sip:anonymous@anonymous.invalid and are receiving a 404/REJECTED response. Non-anonymous calls to the same number works fine.

The DID range is correctly assigned to the only SIP peer profile on the system and that profile has Reject Incoming Anonymous Calls set to No. The only possible suspect I can see is that Alternate Destination Domain FQDN or IP Address is set to the SIP proxy of our SIP provider. Should it be set to this, or even set to anything at all? On other systems I've seen this is not set. What does this setting do?

(the "obvious settings" in the title are the ones that are obvious to me, I fully expect to have missed something simple that others will wonder how I didn't know about them)

[Biggie3300]

Hi grd,
Which carrier are you using, in the SIP menu check you have URI/Number Translation set as URI anonymous@anonymous.invalid set to a valid user DID number.
We have seen the issue with some carriers in AUS, you may also have to set this to the trunk pilot number for it to work.
Regards,

biggie