tambien hise eso juaniquillop pero nada ahi te pego el codigo para q lo veas
$asunto="Recommend Peru For Less";
$cabecera .="From: ".$remitente."<".$mailremitente.">\n";
$cabecera .="Reply-To: ".$remitente."\r\n";
$cabecera .="MIME-Version: 1.0 \r\n";
$cabecera .="X-Mailer: PHP/". phpversion()."\r\n";
//$url="http://".$_SERVER['HTTP_HOST'].$_SERVER['SCRIPT_URL'];
$mensaje="<b>$remitente</b> thought about you while visiting Peru For Less and has recommended the site to you:\n$recibe\n\n
Peru For Less provides quality travel and tours to Peru and Latin America for the best possible prices imaginable.";
mail($mailamigo,$asunto,$mensaje,$cabecera);
echo "<br /><br /><br /><br /><div align='center'><span class='txt'>Thank you, your message has been successfully sent to <br />$mailamigo</span><br /><br /><a
href='javascript
:close()' class='linkspecials1'>Close</a></div>";
}
?>