function toggleDisplay(elt) {
	if (elt.style.display=='block')
		elt.style.display='none';
	else
		elt.style.display='block';
}

function hide(elt) {
	elt.style.display='none';
}

function show(elt) {
	elt.style.display='block';
}

function disable(elt) {
	elt.style.disabled=true;
}

function enable(elt) {
	elt.style.disabled=false;
}

function homepage() {  window.location="default.php";  }
function onePageBack() {  history.go(-1);  }
function clearForm() {  form.reset();  }

/*
http://www.quirksmode.org/blog/archives/2005/10/_and_the_winner_1.html
*/
function addEvent( obj, type, fn )
{
	if (obj.addEventListener)
		obj.addEventListener( type, fn, false );
	else if (obj.attachEvent)
	{
		obj["e"+type+fn] = fn;
		obj[type+fn] = function() { obj["e"+type+fn]( window.event ); }
		obj.attachEvent( "on"+type, obj[type+fn] );
	}
}

function removeEvent( obj, type, fn )
{
	if (obj.removeEventListener)
		obj.removeEventListener( type, fn, false );
	else if (obj.detachEvent)
	{
		obj.detachEvent( "on"+type, obj[type+fn] );
		obj[type+fn] = null;
		obj["e"+type+fn] = null;
	}
}