I just went to Minecraft then I logged in then it said "Minecraft Has Crashed

— BEGIN ERROR REPORT a1dce528 --------
Generated 3/15/13 5:25 PM

Minecraft: Minecraft Alpha v1.2.4_01
OS: Windows 7 (amd64) version 6.1
Java: 1.6.0_14, Sun Microsystems Inc.
VM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Sun Microsystems Inc.
LWJGL: 2.4.2
OpenGL: ATI Radeon HD 4350 version 2.1.8781, ATI Technologies Inc.