Checkbox ajax form posts the word array to email - ajax

Question

I am trying to make a booking form with checkboxes using an existing contact form.js script and mailhandler.php from template monster. All of the text and textarea inputs work fine but the checkboxes only return the word array.
Here's parts of the code:
html
<form action="bin/MailHandler.php" method="post" id="booking-form" >
<fieldset>
<div class="grid_12">
<div class="bookingformwrapper">
<div class="headerbar">WAXING</div>
intrested in:<br/>
<input type="checkbox" name="waxing[]" value="kidum_esek" id="wax1"/>aaa<br />
<input type="checkbox" name="waxing[]" value="mitug_esek" id="wax2"/>bbb<br />
<input type="checkbox" name="waxing[]" value="laikim" id="wax3"/>CCC<br />
<input type="checkbox" name="waxing[]" value="aher" id="wax4"/>DDD<br />
ajax jquery
,submitFu:function(){
var data = { 'waxing[]' : []};
$(":checked").each(function() {
data['waxing[]'].push($(this).val());
});
_.validateFu(_.labels)
if(!_.form.has('.'+_.invalidCl).length)
$.ajax({
type: "POST",
url:_.mailHandlerURL,
data:{
choice:'waxing[]',
name:_.getValFromLabel($('.name',_.form)),
email:_.getValFromLabel($('.email',_.form)),
phone:_.getValFromLabel($('.phone',_.form)),
fax:_.getValFromLabel($('.fax',_.form)),
state:_.getValFromLabel($('.state',_.form)),
message:_.getValFromLabel($('.message',_.form)),
message2:_.getValFromLabel($('.message2',_.form)),
datepicker:_.getValFromLabel($('#datepicker',_.form)),
owner_email:_.ownerEmail,
stripHTML:_.stripHTML
},
success: function(){
_.showFu()
}
})
},
php
<?php
$owner_email = $_POST["owner_email"];
$headers = 'From:' . $_POST["email"];
$subject = 'A message from your site visitor ' . $_POST["name"];
$messageBody = "";
if($POST['waxing[]'] !='nope'){
$messageBody .= '<p>Choice: ' . explode(",", $_POST['waxing[]']);
$messageBody .= '<br>' . "\n";
}
if($_POST['name']!='nope'){
$messageBody .= '<p>Visitor: ' . $_POST["name"] . '</p>' . "\n";
$messageBody .= '<br>' . "\n";
}
if($_POST['email']!='nope'){
$messageBody .= '<p>Email Address: ' . $_POST['email'] . '</p>' . "\n";
$messageBody .= '<br>' . "\n";
}else{
$headers = '';
}
if($_POST['state']!='nope'){
$messageBody .= '<p>State: ' . $_POST['state'] . '</p>' . "\n";
$messageBody .= '<br>' . "\n";
}
if($_POST['phone']!='nope'){
$messageBody .= '<p>Phone Number: ' . $_POST['phone'] . '</p>' . "\n";
$messageBody .= '<br>' . "\n";
}
if($_POST['fax']!='nope'){
$messageBody .= '<p>Fax Number: ' . $_POST['fax'] . '</p>' . "\n";
$messageBody .= '<br>' . "\n";
}
if($_POST['datepicker']!='nope'){
$messageBody .= '<p>Date: ' . $_POST['datepicker'] . '</p>' . "\n";
$messageBody .= '<br>' . "\n";
}
if($_POST['message']!='nope'){
$messageBody .= '<p>Address: ' . $_POST['message'] . '</p>' . "\n";
}
if($_POST['message2']!='nope'){
$messageBody .= '<p>Notes: ' . $_POST['message2'] . '</p>' . "\n";
}
if($_POST["stripHTML"] == 'true'){
$messageBody = strip_tags($messageBody);
}
try{
if(!mail($owner_email, $subject, $messageBody, $headers)){
throw new Exception('mail failed');
}else{
echo 'mail sent';
}
}catch(Exception $e){
echo $e->getMessage() ."\n";
}
?>
This is what gets returned on the email:
Choice: Array
Visitor: Father Christmas
Email Address: father#christmas.com
Phone Number: 01234 567890
Date: 25th December
Address: North Pole
Notes: Mince Pies
Where it says Choice: Array, I need it to give me the values of the selected/checked checkboxes.