Can new comments automatically be posted to Twitter?

I know that a new blog post can automatically be posted on Twitter if you choose that option on the settings tab but is there anyway that new comments made on your blog posts can also be sent to your Twitter feed?

Many times I have come across the beginning of what is a comment on Twitter only to find that the linked page is to a blog post that was really great and one that I would have otherwise missed if it hadn't been for the comment that was automatically feed to Twitter too.

It would really be a great tool if it can be done. Any help would be appreciated!

Edit: Can it also be done on Facebook too? Automatically posting both the blog post and comments that you've made. Links can then be made back to the original post.

Just a thought but it would be an awesome marketing tool!