Searchengine

Hi again, when I was verifying my search funktions on my webpage, I came thinking of, how I will be able to build a search that would be able to find words which are spelled incorrect. I came to this point, 'cause I have a name in my Database called pettersson. Some people believe this guy is written peterson ot petersson. But I want all my visitors to find Him in each cases. I read myself thru Rexular Expressions in MySQL and read thru Fulltext searches thru MATCH() AGAINST() but I think, it would not do what i want. I remember an OpenSource Shop System called Interchange(MiniVend) written in perl, which had failuretollerant search thru the use of egrep. But I dont know how it works. I hope I can find someone here, who has done something like that before. I know it's not easy. So if you could help me a little, i would be very pleased. Have it nice! Sascha