While IMAP protocol defines only one system folder for incoming mail (INBOX), mail clients such as Outlook and Sun Java System Communications Express define their own system folders for drafts, sent mail, and deleted mail. The mail clients have no way of distinguishing those system folders. These system folders are created by different preferred names and localized names according to locale and client software. This causes multiple physical IMAP folders to be created for a system folder if a single email account is accessed by more than one email client (or same email client, but accessed by a different locale machine).
In Outlook the folder naming is:
Deleted Items=Deleted Items
Sent Items=Sent Items
In Communications Express the folder naming is: