I too am having this problem, though for me in 2.0 my client thought the gem armor should be destroying stuff and the server disagreed making me stuck falling into the floor until it redrew the blocks around me. 2.1.1 seems to have fixed that making the client not even think its destroying blocks... This makes me wonder if it was intentional from either Technic or Equivalent Exchange for reasons unknown to me... I suppose having a few people with gem armor could definitively kill a server. Either way i only have a few people online so it would be nice if it worked. I'm pretty handy with java but i don't know much about Minecraft mod coding or where to start. I honestly don't even know where to go to disable EE so it might be a setting there... I will definitively be putting more time into it after finals but for now anyone have any ideas?