Failed to load manifest from minecraft.jar

[Izek]

Yes, I have java 1.6 installed. No, I have not run minecraft, so I do not have a .minecraft/bin folder.

Yes, I downloaded the jar from minecraft.net, and tried to execute it:

[ian@Mune-PC Downloads]$ java -jar ./minecraft.jar
Failed to load Main-Class manifest attribute from
./minecraft.jar

So how do I run it? I don't have a .minecraft folder yet, as said above. Adding the net.minecraft.LauncherFrame doesn't help:

[ian@Mune-PC Downloads]$ java -jar ./minecraft.jar net.minecraft.LauncherFrame
Failed to load Main-Class manifest attribute from
./minecraft.jar