hey guys, what u both have is a known error with the nether ores mod. as far as i know, there is no way to fix it without sacrificing the nether ores mod. if u dont want to get rid of it, i have nothing for you, but if you do, open up the mods folder in the directory of ur tekkit server. find the nether_ores.jar and kill it. start ur server, and u should be fine.