When i updated my minecraft to 1.5 on my mac os x 10.5.8 it would crash here are the details ---- Minecraft Crash Report ----
// Don't do that.

Time: 3/13/13 3:38 PM
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:680)

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 (x86_64) version 10.5.8
Java Version: 1.6.0_26, Apple Inc.
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
Memory: 252018112 bytes (240 MB) / 534708224 bytes (509 MB) up to 1606287360 bytes (1531 MB)
JVM Flags: 3 total; -Xbootclasspath/a:/System/Library/PrivateFrameworks/JavaApplicationLauncher.framework/Resources/LauncherSupport.jar -Xms512M -Xmx1536M
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 X3100 OpenGL Engine GL version 1.2 APPLE-1.5.48, Intel Inc.
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Texture Pack: faithful32pack.zip
Profiler Position: N/A (disabled)
Vec3 Pool Size: ~_ERROR~ NullPointerException: null