jraven90@aol.com on "Is there any way I can end my URL's in .htm"

I am moving a successful ecommerce site to WordPress, but all my old URLs end in .htm
Since WordPress removes periods from URLs, it doesn't look like I can use these old ones.

Because I don't want to lose any hard earned SEO, I would do anything to avoid having to use redirects to new URL's. Is there any hack that would allow me to have my new WordPress URLs end in .htm?