So I'm running the 1.7.10 snapshot 430 on a private server of mine and I was going to use the Item dropper to set up automation for AE2 stuff, but upon placing the item dropper down, placing an item in it and giving it a redstone signal, I get booted from the server, however the server stays up. So I tested it further and put a redstone clock from Project Red to pulse an item out every 2 seconds. BUT this time the whole server crashed (here is the crash report http://pastebin.com/NKjMkpbf) So the issue is whenever you give it a redstone signal with an item inside of it, you either get booted or crash.

Just happened to notice that both project red and codechicken core is mentioned in the report. You should probably try to recreate the crash with only openblocks installed and see if it still works.

Looks like some other mod interferes with item drops from players (tries to capture it via ItemTossEvent). No idea who tries stuff like this, but it's probably bad idea to do it for fake players.

I can fix crash, but item wouldn't show anyway.

Soooo, I forgot about this, then some time later noticed that crash on OpenEye and fixed than OpenModsLib. So closed, I guess. Not sure if blocks will drop, but that not our issue.

Extra info: we use fake players to drop item. Maybe you have some server protection.