How do i change flexes for ragdolls?

I need help with flexes for ragdolls. When i R-click a ragdoll, i have only Bodygroups and Skins.
Does anybody have somewhat addon that can do this?

Help if you can.

You use the face editor for flexes, this is because in source 1 flexes were pretty much only used for facial animation, this is reflected by the fact that a vertex cannot move more than a couple centimeters in a flex.

Ok, Thanks very much, @Grodbert