When you configure E.164 numbering plan you need to make sure that translation pattern is configured properly for end to end communication.
Phone extension need to be configured in following format
\+.! translation pattern is basically for outbound calling (PSTN)
00 is the international prefix and 000 will be matched with routed pattern then 0 will be stripped from route patten.
89XX is the 4 digit users extension and and this translation pattern basically for internal dialing.
When a user dial 8901 Extension it match with 89XX pattern and that will be translated to +4532568901 and then CUCM route the call the to 8901 extension.
- When we need to route a CUC call to extension , Normalization partition should be added in voice mail port CSS.
-Similarly Normalization partition should be added in gateway CSS.
