It's possible, since both use the defense/VP-WP system, but the main problem with this is the flavor stuff. Sure, the system would work out just fine for the mundane classes (though, flavour wise, the psions might be a bit iffy), but what would be the Jedi? Of course, you could just mix and match what you (or your players) wanted, as long as it remains reasonable (so SW Soldiers aren't going side by side with Spycraft Soldiers). It'll definitely take some work, but it's possible (and a heck of a lot easier than trying to use core D&D classes in SW...).