if (typeof window.event != 'undefined')
	document.onkeydown = function(){ 
		if (event.srcElement.tagName.toUpperCase() == 'INPUT')
			return (event.keyCode != 13);
		else if (event.srcElement.tagName.toUpperCase() != 'INPUT' && event.srcElement.tagName.toUpperCase() != 'TEXTAREA')
			return (event.keyCode != 8);
	}
else
	document.onkeypress = function(e){
		if (e.target.nodeName.toUpperCase() == 'INPUT')
			return (e.keyCode != 13);
		else if (e.target.nodeName.toUpperCase() != 'INPUT' && e.target.nodeName.toUpperCase() != 'TEXTAREA')
			return (e.keyCode != 8);
	}