I have written some VBA script to do this *bypass the server's disabling of auto-forward". Basically it mimics the user forwarding the email rather than the server doing an auto-forward.
It's pretty simple:
Sub AutoForwardAllSentItems(Item As Outlook.MailItem)
Dim strMsg As String
Dim myFwd As Outlook.MailItem
Set myFwd = Item.Forward
Set myFwd = Nothing
It's beyond the scope of this post to give detailed instructions, but here's a summary:
Add the above code in the Visual Basic editor of Outlook (Alt-F11 should get your started). Be sure to change email@example.com to the address where you want the mail to go
Tell Outlook to run this code for each inbound message (Tools -> Rules and Alerts -> New Rule -> Check Messages when they arrive -> Next -> YES -> Checkbox "Run a Script" -> Then select the script you just created.
Now Outlook should automatically forward each email you receive, but it won't be blocked by the Admin as an "Auto-forward".