var d = document;

  function getDivHeight(){
    var box = new Array("navAlpha","frame"); //list of DIV ids
    for(x=0;x<box.length;x++){ //determine the tallest div
      h = d.getElementById(box[x]).offsetHeight;
      for(y=0;y<box.length;y++){
        test_h = d.getElementById(box[y]).offsetHeight;
        if(h<test_h) h = test_h;
      }  
    }
    for(x=0;x<box.length;x++) d.getElementById(box[x]).style.height = h +  "px"; //set the height of all divs to the tallest
  }

//Questo script permette di far posizionare in maniera corretta il footer tramite CSS in IE5Win/Mac e Safari
        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 navAlphaHeight = document.getElementById('navAlpha').offsetHeight;
                                        var headerHeight = document.getElementById('header').offsetHeight;
                                        var contentHeight = document.getElementById('content').offsetHeight;
                                        var footerElement = document.getElementById('footer');
                                        var footerHeight  = footerElement.offsetHeight;
										var verticalMarginHeight = 11;

                                        var referenceHeight =  headerHeight + contentHeight ;
                                        if (navAlphaHeight >= referenceHeight) {
                                                referenceHeight = navAlphaHeight;
                                        }

                                       //footerElement.style.position = 'static';
                                       footerElement.style.top = referenceHeight + 'px';
                                }
                        }
                }