Auto weighting single bones?

Hi,

I have a character parented to an armature with automatic weights
I also did some weight painting
Now I want to add some other bones to the armature and to calculate auto weights for them
However if I parent the character to the armature again, the weight is calculated again for all bones, even for the old ones which I have previously painted

So is it possible to have Blender calculate the auto weights only for a single bone or a group of them?
Or alternatively is it possibile to preserve a vertex Groups so when I parent the character to the armature, this vertex group will mantain the weight painting I did manually?

Thanks!

This is something I’d like to see developed, if it doesn’t exist yet!

With the armature in pose mode, 3D view header, check the Weights menu.
Assign Automatic From Bones.

http://www.pasteall.org/pic/show.php?id=66418

WOW! Thanks a LOT!

@dirty-stick: Can the influence be restricted to selected vertex group(s)? That would awesome!

Actually, I must test this, if it works as I understand it now, it’s going to revolutionize my weighting! Hm, I need a good model first… (mutters to himeself)

…tested it, works, however, now I must ask if it normalizes the new influences with old ones? I was a bit unsure.