overchan: cannot write overview

I'm getting this message from one server, running 20030403 CURRENT. I
only get it on a few groups, I seem to get it on every post to these
groups, and it just started. This is a production server, so I'm
hesitant to experiment with more recent versions, since it's otherwise
working.

Any thoughts why that would happen and how I can fix it?
-- 
bill davidsen <davidsen@xxxxxxx>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.