Stop emails tagged as coming through to RT

Hi, we get tickets with [SPAM] in the subject field come through to RT, in
the procmail config, the following is set to stop this

Filter out Potential spam marked up by the Spamchecker.


This will check the email headers for X-org-Spamcheck

Our spam checker tags spam emails with a subject tag [SPAM] and a header
flag “X-org-Spamcheck: Spam”

The spelling of “X-org-Spamcheck” was incorrect and have rectified it, is
this the correct way to filter out SPAM from the RT even if it gets past
the MTA?