function setTall() {
  if (document.getElementById) {
    var divs = new Array(document.getElementById('centrecontent'), document.getElementById('right'), document.getElementById('left'));
    var maxHeight = 0;
    for (var i = 0; i < divs.length; i++) {
      if (divs[i].offsetHeight > maxHeight) maxHeight = divs[i].offsetHeight;
    }
    for (var i = 0; i < divs.length; i++) {
      maxHeight += 20;
      divs[i].style.height = maxHeight + 'px';
    }
  }
}

var Engine = /Gecko/;
var Netscape6a = /Netscape\/6/;
var Netscape6b = /Netscape6/;
var Netscape7 = /Netscape\/7/;
var Firefox = /Firefox\/0/;
var Agent = navigator.userAgent;

if(Engine.exec(Agent) && (Netscape6a.exec(Agent) || Netscape6b.exec(Agent) || Netscape7.exec(Agent) || Firefox.exec(Agent))) {
  window.onload = function() {setTall();}
  window.onresize = function() {setTall();}
}