special prices displayed without VAT on leguide csv

[Davelaar]

I've put this script on my website to create a feed for Leguide.com. It works well, but the special prices are displayed without tax. The normal prices are displayed including tax. How can I change this. I've put the code here. I'm using OSC 2.3.3 I've also put the whole .php script as an attachment.

// Détection des discount price.
$special_query = tep_db_query ('SELECT specials_new_products_price FROM ' . TABLE_SPECIALS . ' WHERE products_id = \'' . $products['products_id'] . '\' AND status = \'1\' ;') ;
if (!$special_result = tep_db_fetch_array ($special_query))
$special_result['specials_new_products_price'] = '' ;

// Calcul des prix.
$regular_price = tep_add_tax ($products['products_price'], tep_get_tax_rate ($products['products_tax_class_id'])) ;
$regular_price = round ($regular_price, 2) ;
if ($special_result['specials_new_products_price'] == '' ) {
$discount_price = '' ;
$sales = 0 ;
} else { //Le produit est en promotion.
$discount_price = round ($special_result['specials_new_products_price'], 2) ;
$sales = 0 ; //Si les promotions sont des soldes, modifiez cette valeur par 1 pour la 1ère démarque, 2 pour la 2ème démarque.