Java sur minecraft / Probleme minecraft

Bonjour, je tente de jouer à Minecraft mais ce message d'erreur apparait: Bad video card drivers!
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Minecraft was unable to start because it failed to find an accelerated OpenGL mode.
This can usually be fixed by updating the video card drivers.



--- BEGIN ERROR REPORT 7fe0271 --------
Generated 18/06/11 18:10

Minecraft: Minecraft Beta 1.5_01
OS: Windows XP (x86) version 5.1
Java: 1.6.0_26, Sun Microsystems Inc.
VM: Java HotSpot(TM) Client VM (mixed mode), Sun Microsystems Inc.
LWJGL: 2.4.2
[failed to get system properties (java.lang.NullPointerException)]

org.lwjgl.LWJGLException: Pixel format not accelerated
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:185)
at org.lwjgl.opengl.Display.createWindow(Display.java:311)
at org.lwjgl.opengl.Display.create(Display.java:856)
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:272)
at net.minecraft.client.Minecraft.run(SourceFile:658)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT 1492ddc1 ----------


Cependant j'ai installé Java... Que faire? Merci d'avance