//use browser sniffing to determine if IE or Opera (ugly, but required)
var isOpera, isIE = false;
if(typeof(window.opera) != 'undefined'){isOpera = true;}
if(!isOpera && navigator.userAgent.indexOf('Internet Explorer')){isIE = true;}

//fix both IE and Opera (adjust when they implement this method properly)
if(isOpera || isIE){
  document.nativeGetElementById = document.getElementById;
  //redefine it!
  document.getElementById = function(id){
    var elem = document.nativeGetElementById(id);
    if(elem){
      //verify it is a valid match!
      if(elem.attributes['id'] && elem.attributes['id'].value == id){
        //valid match!
        return elem;
      } else {
        //not a valid match!
        //the non-standard, document.all array has keys for all name'd, and id'd elements
        //start at one, because we know the first match, is wrong!
        for(var i=1;i<document.all[id].length;i++){
          if(document.all[id][i].attributes['id'] && document.all[id][i].attributes['id'].value == id){
            return document.all[id][i];
          }
        }
      }
    }
    return null;
  };
}


function showAltBlock(defaultBlockId, thisBlockId) {
    document.getElementById(defaultBlockId).style.display="none";
    document.getElementById(defaultBlockId).display="none";
    document.getElementById(thisBlockId).style.display="block";
    document.getElementById(thisBlockId).display="block";
}

function showBaseBlock(defaultBlockId, thisBlockId) {
    document.getElementById(defaultBlockId).style.display="block";
    document.getElementById(defaultBlockId).display="block";
    document.getElementById(thisBlockId).style.display="none";
    document.getElementById(thisBlockId).display="none";
}