ignored invalid download request for product ____, current state = PleaseMirror (still happening in 10.6.8)
Apple's KB article states this was a problem pre 10.6.3. But I've got current multiple 10.6.8 servers that are still experiencing it. Here's the most recent message:
Wed Jun 13 10:04:20 thrall.private swupd_syncd[9067] <Warning>: ignored invalid download request for product 041-4788, current state = PleaseMirror
Original apple KB thread: http://support.apple.com/kb/TS3127?viewlocale=en_US&locale=en_US
Xserve, Mac OS X (10.6.8)