Randy, Are you sure that you need IE in order to view MLS listings? Most MLS sites I have seen recently are now have cross-browser support so that you can use IE or Fx and others (Opera, Chrome, etc.)....
On your phone, though, it may be that it is not the browser, but the browser agent - in other words, the phone is telling the server that it is a mobile device, and the server then says "Sorry, can't help you". Try checking out one of the alternate browsers in the market (a free version first) and see if you can force the MLS site to work from your phone.