Open additional Exchange mailboxes

This feature requires you to be using a Microsoft Exchange Server e-mail account.

If you have delegate access permission for other Exchange mailboxes, you can specify which mailboxes to open in Microsoft Outlook.

1. On the Tools menu, click E-mail accounts, select View or change existing e-mail accounts, click Next, select the Exchange account, and then click Change.
2. Click More Settings, then click the Advanced tab.
3. Under Mailboxes, click Add, and then select the mailboxes to add.

http://office.microsoft.com/en-us/outlook/HP010030561033.aspx