[MC-2004] Crash "ala cannot be cast to ahz"

Random crash while just being on the server. No one else reported crashing.

"
java.lang.ClassCastException: ala cannot be cast to ahz
	at bbq.a(SourceFile:25)
	at bbq.a(SourceFile:10)
	at bby.a(SourceFile:103)
	at bby.a(SourceFile:96)
	at ayy.a(SourceFile:311)
	at ayt.a(SourceFile:853)
	at ayt.b(SourceFile:734)
	at net.minecraft.client.Minecraft.J(SourceFile:604)
	at net.minecraft.client.Minecraft.run(SourceFile:534)
	at java.lang.Thread.run(Unknown Source)
"

Full Log Attached