function addEvent(obj, evType, fn){
  /* adds an eventListener for browsers which support it
     Written by Scott Andrew: nice one, Scott */
  if (obj.addEventListener){
    obj.addEventListener(evType, fn, true);
    return true;
  } else if (obj.attachEvent){
	var r = obj.attachEvent("on"+evType, fn);
    return r;
  } else {
	return false;
  }
}

function checkMail(email) {
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if (filter.test(email)) { 
		return true;
	} else {
		return false;
	}
}

function eventFormChecker() {
	if($F("eventsEmail") == "" || null) {
		alert("Please enter an email address.");
		return false;
	} else if(!checkMail($F("eventsEmail"))) {
		alert("Please Enter a VALID email address.");
		return false;
	}
}

function newsletterFormChecker() {
	if($F("email") == "" || null) {
		alert("Please enter an email address.");
		return false;
	} else if(!checkMail($F("email"))) {
		alert("Please Enter a VALID email address.");
		return false;
	}
}

function randomBackgroundImage() {
	var canvas = document.getElementById("container").className = "";
	
	var ran_unrounded=(Math.random()*5)+1;
	var ran_number=Math.round(ran_unrounded);

	var backgroundImage = "background"+ran_number;
		
	document.getElementById("container").className = backgroundImage;	
}

addEvent(window, "load", randomBackgroundImage);