My friend is having the exact same problem when he joins our private tekkit server (run off my computer) We have tried increasing the allocated ram to no effect.
Launcher/pack Version: .jar launcher/ tekkit
Operating System: win7
Version of Java: I'll post when I find out
Description of Problem: Out of memory error.
Error Messages: I'll post the exact message when I find out.
Link to pastebin of log: I'll post the log ASAP