root/dev/mods/xajax/functions.php

<?php
$xajax->registerFunction("postMail");

function postMail($arry)
{
        // this function handles the posting of mail
        $objResponse = new xajaxResponse();
        $newContent = "response:" .$arry[killmail] ;
        $objResponse->Assign("kill-response", "innerHTML", $newContent);

        return $objResponse;
}