I have 4 combo’s on in a form with there own connector. 3 of them work but one of them keeps displaying an alert box with the xml.
I am using dhtmlx suite 3.6 pro. All the other php combo is written in a similar way and they all work.  
xml code
<?xml version="1.0"?>
<items>
	<item type="settings" labelWidth="150"  inputWidth="250"  position="absolute"  /> 
	<item type="input" name="FIRSTNAME"  bind="FIRSTNAME" label="Firstname:"  labelAlign="right"  inputWidth="200"  labelLeft="25"  labelTop="5"  inputLeft="200"  inputTop="5"  required="true" validate="NotEmpty"/> 
	<item type="input" name="LASTNAME"  bind="LASTNAME" label="Lastname:"  labelAlign="right"  inputWidth="200"  labelLeft="25"  labelTop="27"  inputLeft="200"  inputTop="25"  required="true" validate="NotEmpty"  /> 
	<item type="combo" name="CONTRACT"  bind="CONTRACT" label="Contract / Project:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="50"  inputLeft="200"  inputTop="50" connector="combo/staff/contract.php"  required="true" validate="NotEmpty" /> 
	<item type="combo" name="JOBTITLE"  bind="JOBTITLE" label="Job Title:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="75"  inputLeft="200"  inputTop="75"  connector="combo/staff/jobtitle.php"   /> 
	<item type="combo" name="ENGINEER"  bind="ENGINEER" label="Engineer Licence:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="100"  inputLeft="200"  inputTop="100"  connector="combo/staff/engineer.php"   required="true" validate="NotEmpty" /> 
	<item type="combo" name="PAYE"  bind="PAYE" label="PAYE or Contract:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="125"  inputLeft="200"  inputTop="125" connector="combo/staff/paye.php"   required="true" validate="NotEmpty" /> 
	<item type="input" name="EXT"  bind="EXT" label="Ofiice Phone Ext:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="150"  inputLeft="200"  inputTop="150" /> 
	<item type="input" name="MOBILE"  bind="MOBILE" label="Mobile Phone:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="175"  inputLeft="200"  inputTop="175"  /> 	
	<item type="input" name="AREA"  bind="AREA" label="Area:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="200"  inputLeft="200"  inputTop="200"  /> 
	<item type="input" name="EMAIL"  bind="EMAIL" label="E-mail Address:"  labelAlign="right"  inputWidth="225"  labelLeft="25"  labelTop="225"  inputLeft="200"  inputTop="225" validate="ValidEmail" required="true" /> 
	<item type="hidden" name="STATUS"  bind="STATUS" value="E"  /> 	
	<item type="button" xcommand="save"  value="Submit"  width="125"  inputWidth="125"  inputLeft="75"  inputTop="250"  /> 
</items>php code:
<?php 
require_once("../../codebase/connector/combo_connector.php");
$res=mysql_connect("localhost","*****","*******");
mysql_select_db("DMN_DR");
 
$sql = "SELECT JOBTITLE from tblEmployees group by JOBTITLE";
 
$data = new ComboConnector($res, "MySQL");
$data->render_sql($sql,"JOBTITLE","JOBTITLE,JOBTITLE");
?>