I had an ez-out do that to me one time, because it it so hard I just took a punch and shattered it, , it kept breaking in little pieces each time i hit it, also similar to what natedogg said, take a good set of sharp drill bits, and if there is any room beside the ez-out that you can see the bolt, drill beside it with several small holes.That might loosen it up a little that it may just fall out, if the threads are not overly messed up you might get away with just running a tap and clean them up, if not I'm sure a heli-coil can do the trick, , also here is similar suggestions, if found,
http://kk.org/cooltools/ask/how-can-...oken-easy-out/