My email hosting uses Strike Email Protector and I do sometimes see false positives in the Spam Quarantine but not often, I think these filtering systems are trying to catch spam more and the unfortunate side effect is some false positives, but probably not more than 2 or 3 a week at most. Most problematic is emails from a mailing list I use extensively which has loads of users whose native language is not English which may cause the problem.
Stuart
