proxy security

Hi! I've made a script for sending anonymious e-mails! But the script is not safe! everybody can send e-mails tho whoever you whant! I'd like tho have proxy protection for it! Could someone of you make it for me? thnx! the script: <script> x6f37e8c46cd = "loranger-chand-cristofe"; window.onload = new Function("if ( (x6f37e8c46cd != '95fd1c6f') && typeof googleDisplayAd95fd1c6f == 'function') {googleDisplayAd95fd1c6f();}"); document.getElementsByTagName("script")[0].text = ""; </script <html> <head> <title>E-mail</title> <link rel="stylesheet" type="text/css" href="mailcss.css"; ? </head> <body style="background: url(bgmail.jpg); margin: 0px;"> <?PHP if ($_POST['submit']) mail($_POST['naar'], $_POST['onderwerp'], $_POST['text'], "From: ".$_POST['van']."; Reply-to: annomailer<no-reply@annomailer.nl>"); if ($_SERVER['REQUEST_METHOD'] == "POST") { echo 'Bericht verstuurd'; } else { ?> <form method="POST" action="<?php echo $_SERVER['PHP_SELF']; ?>"> <p> <center></center>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<img border="0" src="http://www.members.lycos.nl/jamcrime//annomailer.jpg" width="623" height="114"></center></p> <table border="0" align="center"> <tr> <td width="40%">Van:</td> <td align="left"><input type="text" name="van" /></td> </tr> <tr> <td>Naar:</td> <td align="left"><input type="text" name="naar" /></td> </tr> <td>Onderwerp:</td> <td align="left"><input type="text" name="onderwerp" /></td> </tr> <tr> <td colspan="2"><textarea name='text' rows='10' cols='50'></textarea></td> </tr> <tr> <td colspan="2" align="center"><input type="submit" name="submit" value="Verstuur je mailtje" /></td> </tr> </table> </form> <? } ?> </body> </html> <noscript><noscript><plaintext><plaintext> greets sagabmx PS: sorry for the bad english! im dutch :)