Actors with defined user and groups

Hi everyone,

What do You think about implement some Actors abilities to pass them
parameters which "user" on which "groups" could own the process? I
call this "Actors sandboxing". What I'm talking about?
In Unix all porocesses have owner (user on whose behalf they work)
and groups (on whose behalf they work). So this could a cool feature
to create Actors with different username/groups then original process.
How use this? I'm engineer and my day of work is: CruiseControl,
Hudson, Git, Subversion, compilers etc... First two is tools for
building wrote in Java. Different projects needs different
permissions: to repository, to disk, to network shares. Writing
CruiseControl or Hudson in Scala using Actors will be cool feature.
But much better will be write CruiseControl/Hudson in Scala using
Actors when each "action" (Actor) could work with other privileges.
This was only example how use such ability. I belive there is a
thousands of ides how take advantage of this feature. What do You
think?