forwarding emails will sa learn?

[Dave]

Hello,
        I got an email that was not tagged high enough as spam, it was a
3.063 when needed was 3.5, so it got through, it is rare. I notice that spam
messages go to username+s...@domain.com can i teach SA that the message is
spam by forwarding the message to that email will it learn for the future?
So far i've just increased the value of the three sa tests that got it.
Thanks.
Dave.