Thanks for the feedback,
In these days I try your solution. It's works well but i've also this issue.
I can mount the image only one time... if I try to mount another time Toast freeze down.
I can recovery the system with a Reboot and also sometimes M.Lion will freeze during the closing windows.
(And then i must press the start up button to force the shut-down)
if you have any ideas I'm going to try that!