function trava_caracter(){
	if(event.keyCode < 48 || event.keyCode > 57){
		event.keyCode = 0;
	}
}
function trava_aspas(){
	if(event.keyCode == 34 || event.keyCode == 39){
		event.keyCode = 0;
	}
}
function popup(pagina,nome,w,h,rolagem){
	LeftPosition = (screen.width) ? (screen.width-w)/2 : 0;
	TopPosition = (screen.height) ? (screen.height-h)/2 : 0;
	settings ='directories=no,fullscreen=no,height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+',location=no,menubar=no,resizable=no,scrollbars='+rolagem+',status=no,toolbar=no'
	win = window.open(pagina,nome,settings)
}