Sorted out, I had added some custom code to the confirm_order.php page that set the PostageType session to 'STANDARD' if the country was 'AU' and 'AIR' for all other countries. The code was:
<?php
// set the service type variable
if ($_SERVER["REQUEST_METHOD"] == "POST") {
if ($_POST["shipping_country"] = 'AU') {
$_SESSION['PostageType'] = 'STANDARD';
} else {
$_SESSION['PostageType'] = 'AIR';
}
}
?>
When it should have been:
<?php
// set the service type variable
if ($_SERVER["REQUEST_METHOD"] == "POST") {
if ($_POST["shipping_country"] == 'AU') {
$_SESSION['PostageType'] = 'STANDARD';
} else {
$_SESSION['PostageType'] = 'AIR';
}
}
?>
$_SESSION['shipping_country'] was being set to 'AU' regardless of which country was selected.
WebAssist should still look into the new API's though, there is no telling how much longer the old one will function correctly.
Thanks for your help Jason.