function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}
function addUnloadEvent(func) {
  var oldonunload = window.onunload;
  if (typeof window.onunload != 'function') {
    window.onunload = func;
  } else {
    window.onunload = function() {
      oldonunload();
      func();
    }
  }
}
/* for browsers with non-native label support */
function focusLabels() {
  if (!document.getElementsByTagName) return false;
  var labels = document.getElementsByTagName("label");
  for (var i=0; i<labels.length; i++) {
    if (!labels[i].getAttribute("for")) continue;
    labels[i].onclick = function() {
      var id = this.getAttribute("for");
      if (!document.getElementById(id)) return false;
      var element = document.getElementById(id);
      element.focus();
    }
  }
}
function mailLink() {
	location.href = "mailto:?body=I thought this link might interest you:\n" + " " + document.title + ". "+window.location; 
}
function prepareLinks() {
	if (!document.getElementsByTagName) return false;
	var lnks = document.getElementsByTagName("a");
	for (var i=0; i<lnks.length; i++) {
		if (lnks[i].className == "popup") {
			lnks[i].onclick = function() {
				popUp(this.getAttribute("href"));
				return false;
			}
		}
	}
}
function popUp(winUrl) {
	window.open(winUrl, "popup", "width=500,height=400");
}

addLoadEvent(prepareLinks);