Unity 7.02 Subscriber import problem

[ahopkins]

I have a new install of Unity 7.02 UM with an Exchange 2003 integration. The integration has gone smooth to a point and I can import users directly from Exchange with no problem. My problem is that once the subscriber has been imported into Unity, if I then edit the subscribers extension number and click save, the subscriber account is changed to an Internet Subscriber account with no mail-store within Unity. I have re-run permissions wizard and everything shows clean, I also have confirmed that the Unity installation account and directory services accounts have been granted Exchange Administrator rights. This seems like a permissions issue but the logs are clean. Once I import a subscriber I can edit any other attribute without any issues. It is only when I edit the subscribers extension that the subscriber is changed to an internet subscriber. Any help in pointing me in the right direction for a posible fix would be greatly appreciated.

[ahopkins]

UPDATE: I had the customer create two user accounts in AD for me to import. One account once imported into Unity works perfectly fine and I can modify all fields. The second account I can modify all fields with the exception of the extension field. With the affected (problem) account once imported from AD I can modify the users name and see it replicated over into Unity. I can also modify the name on the subscriber account and see it replicate over into AD. But if I modify the users extension in Unity and save, the account is orphaned and converted to an Internet Subscriber Account. I ran permissions wizard and everything is clean. Also since AD and Unity sync when changes are made on either side with the name attributes I feel the correct permissions have been set yet I'm stumped as to why changing the extension on one account, orphans the account from AD and the message store. I feel that there must be a difference in how the customer set up the two test account in AD that is causing this problem. Has anyone run into this type of problem? I need something concrete to take back to the customer before they will look into things more on there end.