function leermas(objeto)
{
	var disp = document.getElementById(objeto.id).style.display;

	if (disp=='none')
		disp='block';
	else
		disp='none';
		
	document.getElementById(objeto.id).style.display = disp;
}

function mostrar(id)
{
  obj = document.getElementById(id);
  obj.style.visibility = (obj.style.visibility == 'hidden') ? 'visible' : 'hidden';
}

function ismaxlength(obj)
{
var mlength=obj.getAttribute? parseInt(obj.getAttribute("maxlength")) : ""
if (obj.getAttribute && obj.value.length>mlength)
obj.value=obj.value.substring(0,mlength)
}