I'm tearing my hair out trying to figure out what's causing a conflict in my code ... everything works perfectly in Firefox, but, as usual, IE is totally busted. I've been trying to spot it for weeks and I JUST. CAN'T. FIND. IT.

Can someone lend a helping hand? FYI, the complete page is here:

http://mysarasotashortsale.com/test/

Code:
<div class="sos_wrap">
  <div id="sos_form">
    <div id="sos_form_div1">
      <h3 style="text-align:right; margin-right:20px">STEP ONE</h3>
      <div class="sos_button" id="sos_div1_button">
        <h4>GO TO STEP 2 &raquo;</h4>
      </div>
      <table width="690px">
    [ ... lots of boring stuff :) ]
            </table></td>
        </tr>
      </table>
    </div>
    <div id="sos_form_div2">
      <h3 style="text-align:right; margin-right:20px">STEP TWO</h3>
      <div class="sos_button" onClick="javascript:jQuery(this).submit();">
        <h4>SUBMIT</h4>
      </div>
      <table width="690px">
  [ ... lots of boring stuff :) ]
      </table>
    </div>
  </div>
</div>
<script>
function notEmpty(elem, helperMsg){
	if(elem.value.length == 0){
		alert(helperMsg);
		elem.focus(); // set the focus to this input
		return false;
	}
	return true;
}
</script>
<script>
jQuery("#sos_div1_button").click(function(){
if(notEmpty(document.getElementById('PropertyAddress'),'Address is a required field.')){
if(notEmpty(document.getElementById('PropertyCity'),'City is a required field.')){
if(notEmpty(document.getElementById('PropertyState'),'State is a required field.')){
if(notEmpty(document.getElementById('PropertyZip'),'ZIP code is required.')){
		jQuery("#sos_form_div1,#sos_form_div2").animate({left:"-=100%"}, "slow");
		}}}}});
</script>