In the case that you actually have an obscure type of threading on your BB, which I find highly unlikely, Sheldon Brown again comes to the rescue! His shop sells the new YST threadless bottom brackets. They are only $20 and will fit pretty much any BB shell, including those with damaged threads... http://sheldonbrown.com/harris/bottombrackets.html#yst
Prepping the frame for one of these BBs requires chamfering the BB shell with a shop tool, should cost maybe $10 at a well-equipped shop. This is a great product from what I have heard.