function isEmailAddress( s )
{
	var filter=/^[A-Za-z][A-Za-z0-9_]*@[A-Za-z0-9_]+\.[A-Za-z0-9_.]+[A-za-z]$/;

	if (filter.test(s))
		return true;
	
	return false;
}

function abreVentana(url,ancho,alto)
{
	var left = (screen.availWidth - ancho)/2, top = (screen.availHeight - alto)/ 2;
	var imgWin = window.open(url, "", "width=" + ancho + ",height=" + alto + ",left=" + left + ",top=" + top);
}

function pp()
{
	abreVentana("/pp.php",450,500);
}

function al()
{
	abreVentana("/al.php",450,200);
}