ajuda erro no minecraft pirata quando fasso o login

toda vez que eu logo no minecraft pirata (para mac) ocorre esse erro

Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem.

--- BEGIN ERROR REPORT 7cf3a456 --------
Generated 30/05/12 21:57

Minecraft: Minecraft 1.2.5
OS: Mac OS X (i386) version 10.6.2
Java: 1.6.0_15, Apple Inc.
VM: Java HotSpot(TM) Client VM (mixed mode), Apple Inc.
LWJGL: 2.4.2
[failed to get system properties (java.lang.NullPointerException)]

org.lwjgl.LWJGLException: Could not create pixel format
at org.lwjgl.opengl.MacOSXPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.MacOSXPeerInfo.choosePixelFormat(MacOSXPeerInfo.java:55)
at org.lwjgl.opengl.MacOSXPeerInfo.(MacOSXPeerInfo.java:50)
at org.lwjgl.opengl.MacOSXCanvasPeerInfo.(MacOSXCanvasPeerInfo.java:49)
at org.lwjgl.opengl.MacOSXDisplayPeerInfo.(MacOSXDisplayPeerInfo.java:48)
at org.lwjgl.opengl.MacOSXDisplay.createPeerInfo(MacOSXDisplay.java:246)
at org.lwjgl.opengl.Display.create(Display.java:854)
at org.lwjgl.opengl.Display.create(Display.java:784)
at org.lwjgl.opengl.Display.create(Display.java:765)
at net.minecraft.client.Minecraft.a(SourceFile:236)
at net.minecraft.client.Minecraft.run(SourceFile:657)
at java.lang.Thread.run(Thread.java:637)
--- END ERROR REPORT d1e8f004 ----------

me ajudem por favor!!!