Go to "Board index" and look at the Birthdays list. See if you can spot the spambot names (hint: it's 90% of them).
Though I agree that the moderation is a bit harsh as it took like 3 days and 15 posts to get my clearance. Sometimes dedicated spammers can be tricky but it really doesn't take that
many posts to recognize a legitimate user.
edit: you will eventually not need to be filtered, just in case I wasn't clear on that