I remember issue with Jabber that required the user to logout everyday in order to prevent stale connection with the UC nodes. Does anyone recall? 

This is most likely due to iPhone OS disconnecting the traffic when Jabber is idle in the background. Cisco has fix for this in 11.5SU3 using push notification. After upgrading CUCM/IMP, also VCS if MRA is being used, for every call/IM setup to Jabbe...

Could you please attach the running configs on the voice gateway? 

Hi Marko,   Could you provide with the call trace from RTMT from your test call? Also, does it disconnect after the destination picks up the call? 

Yup. Let's assess both inbound and outbound separately.    I'm guessing inbound from outside is on DP 99. After receiving this, where do you want to send the call? This needs to be specified since currently, all of your DPs are using .T as a destinat...