mod_rewrite -> redirect to index.php in a subfolder

[Snaggy]

here's my problem: I want to have everything redirected to index.php
but for images and javascript. The point is that I'm in a subfolder of
the web server:

http://localhost/mySite/home --> http://localhost/mySite/index.php/home
(rewritten)
http://localhost/mySite/script.js --> http://localhost/mySite/script.js
(not affected)
http://localhost/otherSite/home --> http://localhost/otherSite/home
(not affected)

any help would be appreciated!
thanks
Snaggy