> I was able to narrow this down to the BlockUI plugin, and more > specifically, the GrowlUI function within it. These growl alerts show > up on every page load, so it was explained why I saw so many 404's in > the logs. Debugging the script to find the source of the "null" > requests was a lot harder, but I finally traced it down to the default > CSS used for the Growl overlays rendered by BlockUI.
Good catch, Jeremy! This is now fixed in BlockUI v2.26. http://www.malsup.com/jquery/block/#download
