Done crashing while logging in

Code:

java.lang.IllegalArgumentException: Default value cannot be lower than minimum value!
	at net.minecraft.entity.ai.attributes.RangedAttribute.<init>(SourceFile:14)
	at net.minecraft.client.network.NetHandlerPlayClient.func_147290_a(NetHandlerPlayClient.java:1630)
	at net.minecraft.network.play.server.S20PacketEntityProperties.func_148833_a(SourceFile:71)
	at net.minecraft.network.play.server.S20PacketEntityProperties.func_148833_a(SourceFile:15)
	at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
	at net.minecraft.client.multiplayer.GuiConnecting.func_73876_c(SourceFile:78)
	at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1661)
	at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:973)
	at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:898)
	at net.minecraft.client.main.Main.main(SourceFile:148)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
	at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

I was walking in farm world, suddenly I went to the air and I was bouncing down and up till it smashed me to the ground and killed. Dont know if it was kind of weird bug or some stupid magic mode. I respawned, went to farm world teleporter and it crashed. Now it is crashing always when I try to log in. Help would be appreciated. Thank you.

 

me and Back2_reality are having the exact same problem, crashes on login, cant fix, i think the farm world needs a reset, or to be blocked off as this will create work for the staff...