Appologies for not coming back to this post. I completely forgot about it to be honest, but I could not find the program I was looking for, and admit defeat on this one, but hopfully Loqi's information may be of some use to you. LOQI's answer to this (in a previous post) is as follows :
www.patches.org used to have the answer to your problem. There are two programes that I know of which I got from them years ago, one of which is called FLmask, and the other may have been flmask32. Try googling, but with caution, 'cos there are all sorts of nasties in this area.
Credit to Loqi for this information.