function getWindowHeight() {
   var windowHeight=0;
   if (typeof(window.innerHeight)=='number') {
     windowHeight=window.innerHeight;
   }
   else {
     if (document.documentElement&&
       document.documentElement.clientHeight) {
         windowHeight=
           document.documentElement.clientHeight;
     }
     else {
       if (document.body&&document.body.clientHeight) {
         windowHeight=document.body.clientHeight;
       }
     }
   }
   return windowHeight;
 }

function setFooter() {
   if (document.getElementById) {
     var windowHeight=getWindowHeight();
     if (windowHeight>0) {
       var contentHeight=
         document.getElementById('content').offsetHeight;
       var footerElement=
         document.getElementById('footer');
       var footerHeight=footerElement.offsetHeight;
       if (windowHeight-(contentHeight+footerHeight)>=0) {
         footerElement.style.position='relative';
         footerElement.style.top=(windowHeight-
           (contentHeight+footerHeight))+'px';
       }
       else {
         footerElement.style.position='static';
       }
     }
   }
 }