Taint mode is definatly a curious thing, if you are looking for good information the tutoral recomended above was my way into to it. also I have asked several dozen questions regarding taint mode here, and almost every response I recieved was worth its weight in gold, so you may want to look at what has been recomeded to me in the past for some quick and dirty breif information.
jcpunk
all code is tested, and doesn't work so there :p (varient on common PM sig for my own ammusment)