Usually when the chain rubs against the front der in the 3 top gears it rubs against the RH side (outside). This can be fixed by unscrewing the H limit screw on the fr der, and possibly tightening the gear shift cable by unscrewing the barrel adjusters a bit. If it really is rubbing on the LH side (inside) you would have to do the opposite. See what Sheldon Brown has to say about it
http://www.sheldonbrown.com/articles.html