We've had a problem with spam comments going in for days gone by for several years, even though the comments for a day shut off with midnight rollover. I guess they count for Google points or something. I've been afraid to tackle them because I was afraid of killing legitimate comments along with the machine-generated crap. Instead I just went in now and then and dumped them by hand.Last night I dumped about 87,000 of the stinkers. I hadn't cleaned house in a week or so, but that was still too significant to ignore. So I wrote a routine to divert them to a holding table, which I can clean out periodically.
If you make a comment and it's lost (which doesn't include Smoked or Spam Copped or otherwise sink trapped) let me know and I'll see if it got diverted. If we go for a month or so without losing any real comments the crap can go directly into the bit bucket.