Unless you are doing something unusual, you shouldn't need a script for that. Entourage gives you the choice to reply using the account a message was sent to (assuming it's in your accounts list, I would imagine), or replying using your default account.
Edit > Preferences > Mail & News : Under "Reply & Forward", disable "Reply using the default account"
I do believe that will get what you're after...
I think he wants it for an SMTP-only + dummy redirected set-up. I might be wrong. See my last post for a solution if that is the case.
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Paul Berkowitz
