It is important that we train the filter based on as accurate copy of the email as possible. You should therefore resend the message to the spam filter training addresses rather than forward them. (Forwarding changes the characteristics of the mail enough that it's not useful for training purposes.)
Spam not tagged as spam should be resent to spam<AT>spamfilter.com. Mail erroneously tagged as spam should be resent to ham<AT>spamfilter.com. Mail resent to these addresses is automatically scanned and the Bayesian filter's database updated.