On April 15th 2010, the ClamAV have started distributing a special signature in the virus definition files that kills older, pre-0.95 versions of ClamAV engine. The last OpenBSD release with an affected version of ClamAV engine was 4.5, which is not supported anymore since November 1st 2009.
Nevertheless, if you happen to run 4.5 or (gasp) even something older, it will require some attention and/or backporting of a newer engine. Now this is a very good opportunity to update the box instead, it will probably require less time and effort :) Mitja (whose only notification was a bunch of support calls that "the mail doesn't work")
