Moving a mailbox: losing the dumpster content
When you delete an item from your mailbox, the item will be kept on the dumpster for as long as configured for your mailbox or for the mailbox database to which your mailbox belongs. The default deleted item retention time in Exchange 2007 is set to 14 days. Users are able to recover items from the dumpster using both Microsoft Office Outlook and Microsoft Outlook Web Access. As administrator you need to keep in mind however that when you move a mailbox from one mailbox database to another mailbox database, that the content of the dumpster is not moved for that mailbox and therefore lost.