Cody's dashboard

Feed My Inbox has been a great way for us to give our readers the ability to get RSS in their inbox from our website. But we'd also like to give people the opportunity to subscribe to an RSS feed via email. It would seem that we simply need to add the subscription form to an email message. Like this:

<form target="fmi"> <input name="email" type="text" /> <input name="feed" type="hidden" value="http://twitter.com/statuses/user_timeline/57043847.rss" />
<input type="submit" value="Submit" /> </form>

But unfortunately, it says, "A valid URL is required" Any idea how we could email our form for people to subscribe?