function disableCtrl(evt)
{
	var disabled = {a:0, c:0, x:0, v:0};
	var ctrlMod = (window.event)? window.event.ctrlKey : evt.ctrlKey;
	var key = (window.event)? window.event.keyCode : evt.which;
	key = String.fromCharCode(key).toLowerCase();
	return (ctrlMod && (key in disabled))? false : true;
}

function limparCampo(id){
	document.getElementById(id).value="";
}