IPPhone---CME--------RouterwithCUE.
You can set up h323 dial-peers on the CME gateway and then point it to the router which has CUE installed. (vice versa). Make sure you give the following command in the RouterwithCUE.
voice service voip
allow-connection h323 to sip
allow-connection sip to h323
On the dial-peers you should use codec g711ulaw. If you use g729 then you will need to setup transcoders to transcode the g729 call before sending it to CUE.
Also you need to set up dial-peers for the MWI numbers (8000.... and 8001....) from the router that hosts CUE back to the CME Router.
HTH
Sankar
PS: please remember to rate posts!
Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus