I have a CUCM 10.5.2 configured on my customer, they have a integration via H323 with gateway Alcatel system.
In CUCM I have gateway H323 configuration to Alcatel.
Happens that a call from IP phones Cisco to phones on Alcatel don't have ringback, the call complete and de audio works in both directions, but IP phone Cisco don't received ringback.
I have MTP checked, inbound faststart, outbound faststart with codec G729 checked.
I collect from RTMT a SDL trace log from a call that does't have ringback.
Any one already see somethig like that?
I was facing the same issue and it started working after checking "Enable Outbound FastStart" in the H323 trunk to Alcatel