function checkMail(x, filter)
{
	if (filter.test(x))	return true;
	return false;
}


function validar_contacto(form)
{
	if(form.nombre.value == '' || form.nombre.value == 'Nombre?') {
		form.nombre.className = 'form_e';
		form.nombre.value = 'Nombre?';
		form.nombre.focus();
		return false;
	}
	if(form.apellido.value == '' || form.apellido.value == 'Apellido?') {
		form.apellido.className = 'form_e';
		form.apellido.value = 'Apellido?';
		form.apellido.focus();
		return false;
	}
	if(form.telefono.value == '' || form.telefono.value == 'Telefono?') {
		form.telefono.className = 'form_e';
		form.telefono.value = 'Telefono?';
		form.telefono.focus();
		return false;
	}
	if(form.email.value == '' || form.email.value == 'E-mail?') {
		form.email.className = 'form_e';
		form.email.value = 'E-mail?';
		form.email.focus();
		return false;
	}
	ex_email = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if(!checkMail(form.email.value, ex_email)) {
		form.email.className = 'form_e';
		form.email.value = 'E-mail?';
		form.email.focus();
		return false;
	}
	if(form.consulta.value == '' || form.consulta.value == 'Consulta?') {
		form.consulta.className = 'form_e_2';
		form.consulta.value = 'Consulta?';
		form.consulta.focus();
		return false;
	}
		
	document.getElementById('contacto').submit();
}

var id_marca;
var marca;
var id_marca_o;
var marca_o;
function marca_on(id_marca, marca){
document.images[id_marca].src=marca;
}
function marca_out(id_marca_o, marca_o){
document.images[id_marca_o].src=marca_o;
}