function validar(formulario, rname, remail, rmsg)
{
	var name,mail,msg;
	if( formulario.nombre.value.length == 0 )
	{
		alert(rname);
		name = false;
	} 
	else 
		name = true;
	if( /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(formulario.email.value) )
		mail = true;
	else 
	{
		alert(remail);
		mail = false;
	}
	if( formulario.coment.value.length == 0 )
	{
		alert(rmsg);
		msg = false;
	} 
	else 
		msg = true;
	
	if( mail && name && msg )
		return (true);
	else
		return (false);
}