How can I use my Ma.gnolia RSS feed to post to my Tumblr blog?

How can I use my Ma.gnolia Feed to post to my Tumblr Blog? -- Background: I have a microblog, I want this micro blog to pull the latest links I publish to Ma.gnolia. However, when I put in this address "http://ma.gnolia.com/people/aaronmclay/bookmarks" in tubmlr it says the feed is invaild. The same goes for the RSS Url. The only error message I get is "Not a valid feed." What am I missing.