CUCM 11.5 Allow Anonymous Calls

[mumbles202]

I've been asked to allow Anonymous calls in CUCM across a SIP trunk from the PSTN.  I don't have the option checked to reject Anonymous calls on the DN, however calls are still getting dropped.  Looking through the logs in CUCM I'm getting a 404, but if i redial the same number and remove the *67 on the call it completes fine. Do i need to change the Validate Refer-to URI to Never Validate for this to work?

[mumbles202]

So an observation.  If i use the previously configured CSS for the gateway, the incoming call comes in a 91Anonymous, but does ring in fine.  If I use a call filtering CSS w/ the next hop being a CSS who in turn points to the gateway CSS I get the error.  I do have a prefix in place to prepend "91" to incoming calls so users don't have to hit "Edit Dial" when returning a missed call so perhaps that in combination w/ the call filtering is causing the issue? I do have both a "!" and "" translation in the CSS for screening the calls.