I believe I just sall a pull request for this on jgarzik's github account.
I have a question... why require passwords at all?
If you are worried about somebody stealing them.. why not simply do away with passwords in general and tell people to keep their miner usernames secret like a password?
As you said, what's the big deal with somebody submitting shares in your name?
Ultimately its psychological it seems a lot of n00bs tend to think that their miners can get over ran with out a passwords. I get funny questions like that all day. but can't blame them we were all n00bs once