So when i try to log onto my account or my brother's on this computer, it shows the mojang sign and then a wall of dirt blocks, then it crashes, here is the crash report: ---- Minecraft Crash Report ----
// There are four lights!

Time: 3/19/13 11:59 AM
Description: Unexpected error

java.lang.IllegalStateException: Function is not supported
at org.lwjgl.BufferChecks.checkFunctionAddress(BufferChecks.java:64)
at org.lwjgl.opengl.GL13.glActiveTexture(GL13.java:121)
at bii.a(SourceFile:438)
at bfy.f(SourceFile:114)
at bfy.b(SourceFile:98)
at net.minecraft.client.Minecraft.l(SourceFile:1056)
at net.minecraft.client.Minecraft.K(SourceFile:572)
at net.minecraft.client.Minecraft.run(SourceFile:524)
at java.lang.Thread.run(Thread.java:613)

A detailed walkthrough of the error, its code path and all known details is as follows:
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– System Details –
Details:
Minecraft Version: 1.5
Operating System: Mac OS X (i386) version 10.4.11
Java Version: 1.5.0_19, Apple Computer, Inc.
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), "Apple Computer, Inc."
Memory: 478872024 bytes (456 MB) / 532807680 bytes (508 MB) up to 1065484288 bytes (1016 MB)
JVM Flags: 3 total; -Xbootclasspath/a:/System/Library/PrivateFrameworks/JavaApplicationLauncher.framework/Resources/LauncherSupport.jar -Xms512M -Xmx1024M
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Suspicious classes: No suspicious classes found.
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
LWJGL: 2.4.2
OpenGL: Intel GMA 950 OpenGL Engine GL version 1.2 APPLE-1.4.56, Intel Inc.
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Texture Pack: Default
Profiler Position: N/A (disabled)
Vec3 Pool Size: ~_ERROR~ NullPointerException: null

it isnt one of our accounts that is causing an issue because they work on my other computer