You can configure Unity to make a copy of messages deleted over the phone in the Exchange "deleted items folder" for that subscriber. You'll find this on the Class of Service "messages" page. You cannot get at deleted items over the phone, but you can get at them via Outlook and drag them back to the inbox if a user accidentally "fat fingered" a message delete over the phone.
By default this COS setting is off which means a copy is not made and the message is permanantly deleted. There's no way to retrieve a message that's been deleted like this.
Jeff Lindborg
Unity Product Architect/Answer Monkey
Cisco Systems
lindborg@cisco.com
http://www.AnswerMonkey.net (new page for Unity support tools and scripts)