script to delete outlook mailbox account

[projector1]

We move over to zimbra today.........
Our staff use outlook 2003 to access their emails. We have configured outlook with their new mailbox account details. I am looking for a script to delete their sina account from outlook to prevent any confusion.
I shall be asking the staff to run the script manually.
If this is not possible then a script to set email account named My Zimbra Email as the default account.
We do not have an exchange server and all cleints are xp pro sp2
Thanks