outlook forwarding rules

Can anyone help with what I'm sure is a simple problem?
We have an exchange server for our e-mail at work.
I am trying to set rules that forward a colleagues work e-mails to a gmail account when he is not in the office.
I am a windows user and rules are simple to implement in outlook for windows and a dog to implement in outlook for osx.
I have managed to set a rule that forwards e-mail to the account but it wont stop. (its a little like the sorcerers apprentice as it is factoring by 2 each time it forwards the mail).
Can anyone help with a simple solution to this problem?

There's been a lot of discussion about Outlook's forwarding of mail. This is of course in regard to Office 2011. Apparently the rules settings do not work as they should. I recommend going to the MS Mac Office forums and see what they have for resolving the problem and any work arounds. Here's the direct LINK.

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