Please look at the article here on how to set up mail forwarding for an exchange mailbox,to forward to an external ID.
http://exchangepedia.com/2008/02/how-to-forward-mail-to-an-external-email-address.html
Please look at the article here on how to set up mail forwarding for an exchange mailbox,to forward to an external ID.
http://exchangepedia.com/2008/02/how-to-forward-mail-to-an-external-email-address.html