I believe the answer is yes. Assuming a CUCM integration given your CTI ports you should be able to assign E164 to patterns on those devices inside CUCM. CUE itself has an E164 field under the user that allows you to provide not only and internal extension, but also a E164 number for user identification.
The CTI ports are being connected by CUCM so I dont' think the CUE device even sees the dialed CTI number. It just sees the CTI communication from CUCM to enable the call. I don't think you'll have any issues there.
I'm not sure if the actual E164 number can be imported in use in the Primary Extension field. There is an option for other where you might be able to configure it.
If you can't I would configure the E164 number under the Primary E164 Number field. This should allow calls to that number to be routed to the mailbox and calls in from the number to be forwarded to the login menu.
In this document they have some more info that covers how to use the E164 field to accomplish being recognized from nubmers other than the DN. In your case the DN is the E164 number, but they may still apply if necessary.
I'm not able to access my old voice mail messages all of a sudden. The recording says something like 'the message is currently not available'. This has never happened before in all the years I have been using this system. I have t...