The only work around is to use Auto-Text for signatures, not the auto signature. That way, when you e-mail the blog, no unnecessary info goes in.
And if you get a personal e-mail, you can put your personal signature, work, etc.
I used to use an interface where you e-mail and it puts it on a website (similar to a blogger) Flex Window www.flexwindow.com, and it had some code that you could put in to ignore signatures and post in html...worth looking into as well.