Ragdoll physics problems

Hello.
Recently, I made a ragdoll for my game, but I have a problem in the physics configuration.
The behavior of the ragdoll isn’t realistic: it starts to shake when it is in the floor, etc.
I try to configurate the physics values, but i don’t understand very well every parameter, and I don’t know how configurate the ragdoll physics for achieve a realistic operation.
How i must configurate the values (mass, radius…) of the ragdoll for improve it?
This is the blend.
http://www.pasteall.org/blend/28439

You have your collision bounds set to 0 which Blender doesn’t really like. Put a small amount in there and it works, I did like .01. (You can change the bounds on one piece, select all of the ragdoll pieces, and do a copy physics properties command to save a little time.)

Ok, thanks for the advice. It works better now.
Better, but not perfect. It shakes a bit yet. The mass propertie, in wich value I must put it?

I leave the mass at the default 1. I haven’t really messed around with it yet. You might need to scale the pieces a little bit to get it to work better. I usually just do a bunch of guessing and checking with the size until it looks pretty good.

Ok, but, scale it in edit mode, or in object mode?