Error: "java.lang.NullPointerException"

[FeistyMonkey]

Title: Error: "java.lang.NullPointerException"

Version: 3.1.2

OS: OSX Mountain Lion

Java Version: Java 7 Update 17 (Using a 1.6.0.jdk Launcher)

Description of Problem:

Whenever i try to connect to a certain server i immediately get disconnected. I think it has something to do with the item "Monitor (Redpower)", because when i crafted it my game crashed.

Error Messages:

Internal exception: java.lang.NullPointerException

Error Log:

[13:40:18] [sEVERE]	java.lang.NullPointerException

[13:40:18] [sEVERE]		at abs.b(SourceFile:227)

[13:40:18] [sEVERE]		at abl.a(SourceFile:29)

[13:40:18] [sEVERE]		at abs.a(SourceFile:155)

[13:40:18] [sEVERE]		at lg.e(NetworkManager.java:227)

[13:40:18] [sEVERE]		at lg.c(NetworkManager.java:389)

[13:40:18] [sEVERE]		at rl.run(SourceFile:76)