you missed this part from the thread i linked to:
<?php echo((isset($_POST["toAddresses[]"]))?$_POST["toAddresses[]"]:"") ?>
these should be removed from the binding code:
<?php echo((isset($_POST["toAddresses"]))?$_POST["toAddresses"]:"") ?>
on your page, find the following line of code:
$RecipArray[$CurIndex ][] = "".((isset($_POST["toAddresses[]"]))?$_POST["toAddresses[]"]:"") ."";
and change it to:
$RecipArray[$CurIndex ][] = "".((isset($_POST["toAddresses"]))?$_POST["toAddresses"]:"") ."";