Problems W\ Paint Blend Shape Weight

Hello all!

I'm experiencing problem using the paint blend shape weight tool in Maya 7. I would assume that I did somthing wrong, but it works sometimes and sometimes not!

Here is what is happening:

-no node appear in the node list of the tool option menu,
-the base shape is never paintable.
- Restart and it works and then ...not!

The help doc does not help me... Has anybody experienced the same problems in maya 7?

Thanx
Remi

Ok, great! Now maya is crashing systematically when I try to flood the wright on the base shape!
I hope Autodesk will be able to fix this soon! :\

Remi