Hi Eric,
I believe this is the expected behavior. Have a look below;
Mailbox-Size Quotas and Message Aging in Connection
By default, when a user deletes a voice message in Connection, the message is sent to the Connection
deleted items folder and synchronized with the Outlook Deleted Items folder. When the message is
deleted from the Connection deleted items folder (the user can do this manually, or you can configure
message aging to do it automatically), it is also deleted from the Outlook Deleted Items folder.
From;
http://www.cisco.com/en/US/docs/voice_ip_comm/connection/8x/design/guide/8xcucdg032.pdf
There is a note pertaining to message retention further down the page in this doc, but since
I have zero Exchange knowledge I can't tell what or how it's done (sorry my friend!)
Cheers!
Rob
"Talk about a dream
Try to make it real"
- Springsteen