Adding a new textbox to send?!

1

currently i have "sender email/message subject/ and message…

i want to add “phone”

how?..iv tried so many thiings…and now i can get it to work when testing it on my computer…but when i put it on the web…it wont send the “phone”…heres my PHP…

<?php


Note: most servers require that one of the emails (sender or receiver) to be an email hosted by same server, 
so make sure your email (on last line of this file) is one hosted on same server.
--------------------------- */


// read the variables form the string, (this is not needed with some servers).
$subject = $_REQUEST["subject"];
$message = $_REQUEST["message"];
$sender = $_REQUEST["sender"];


// include sender IP in the message.
$full_message = $_REQUEST["phone"]. "

" . $message;
$message= $full_message;

// remove the backslashes that normally appears when entering " or '
$message = stripslashes($message); 
$subject = stripslashes($subject); 
$sender = stripslashes($sender); 

// add a prefix in the subject line so that you know the email was sent by online form
$subject = "Contact form ". $subject;
$message = $_REQUEST["phone"]. $message;

// send the email, make sure you replace email@yourserver.com with your email address
if(isset($message) and isset($subject) and isset($sender)){
    mail("andy@akmdesign.net", $subject, $message, "From: $sender");
}
?>

heres my AS

stop();
send_btn.onRelease = function() {
    my_vars = new LoadVars();
    my_vars.sender = email_box.text;
    my_vars.subject = subject_box.text;
    my_vars.message = message_box.text;
    if (my_vars.sender != "" and my_vars.subject != "" and my_vars.message != "") {
        my_vars.sendAndLoad("http://www.akmdesign.net/mail_form.php", my_vars, "POST");
        gotoAndStop(2);
    } else {
        error_clip.gotoAndPlay(2);
    }
    my_vars.onLoad = function() {
        gotoAndStop(3);
    };
};
email_box.onSetFocus = subject_box.onSetFocus=message_box.onSetFocus=function () {
    if (error_clip._currentframe != 1) {
        error_clip.gotoAndPlay(6);
    }
};

HELP!!