I'm having the same problem on my PDA?
Any chance of an answer to this because I can't answer posts only see them in this format.
My workaround on the iPod Touch is to log in correctly once by entering the password. Then, each time when it loads the BWhat page (or when I log in to BWhat), I tell it no, I don't want to change my password. This seems to avoid replacing the correct password I've entered.