install.js????

hello friends,

i am confused about install.js script. Is it true that install.js will
be deprecated in future versions of firefox?

I wanted to distribute an extension which installs an windows
application on users' machine. So after i install my extension, i
should be able to launch an installer which installs my windows
application..basically putting the windows application in the right
windows direcytory and write the path in the registry.

I was aware that this could be done using install.js script using
XPInstall and use Install Object
But if i cannot use install.js i do not know any other method to do
this! 

Please help!!!!