Mail.app Doesnt know how to forward

[twitchg3]

I set up a "rule" or filter in the Mail.app in OSX and set it so that it would match the Subject and then set it to Forward to a different address and then delete the message. All is fine on the deleting of the message, so it doesnt stay in Mail.app but my prob now is that when it forwards the message to the other account, it sends 2 at a time. I came to work this morning and for some reason, there were 500+ emails in that other account. Apparently mail.app had sent them over and over. Anybody else have this issue or a fix? Thanks