I may have one more clue - we're getting something like 20,000-30,000 page views a day and it could be that it's asking too much of the UBB, causing page errors. I think that the perl mapping errors were contributing but may have only been one of a few issues. For example we still get random images, but not nearly as often, and the ISEs are practically gone. After upgrading to 6.1.0.4, I have a slow board and occasional "This routine has confused my poor little brain! at ubb_lib.cgi line 1854" errors. I'm already getting some help for this, just thought I'd pass on the info.
