I’ve got two IMAP Entourage accounts. Spam Sieve works on one and not the other. I looked at the working account and the non-working account to try to see what was different. They appear the same. I went through the self checks and can’t find what’s wrong.
That probably means that your Entourage rule is not set up correctly. Please follow the setup instructions again or post a screenshot showing the rule that doesn’t work.