Index: /controller/wpsg_OrderController.class.php
===================================================================
--- /controller/wpsg_OrderController.class.php	(revision 7250)
+++ /controller/wpsg_OrderController.class.php	(revision 7251)
@@ -1320,6 +1320,9 @@
 		            if ($_REQUEST['add_eu'] === '1') $eu = true;
 		            else $eu = false;
+			
+					$product_index = false;
+		            if (wpsg_isSizedInt($order_product_id)) $product_index = $this->db->fetchOne("SELECT `product_index` FROM `".WPSG_TBL_ORDERPRODUCT."` WHERE `id` = '".M1::q($order_product_id)."' ");
 		            
-					$oCalculation->addProduct($_REQUEST['add_price'], $this->shop->getBackendTaxview(), $oProduct->mwst_key, $_REQUEST['add_amount'], $product_key, false, $order_product_id, $eu);
+					$oCalculation->addProduct($_REQUEST['add_price'], $this->shop->getBackendTaxview(), $oProduct->mwst_key, $_REQUEST['add_amount'], $product_key, $product_index, $order_product_id, $eu);
 			
 					$oCalculation->toDB($_REQUEST['edit_id']);
Index: /lib/wpsg_basket.class.php
===================================================================
--- /lib/wpsg_basket.class.php	(revision 7250)
+++ /lib/wpsg_basket.class.php	(revision 7251)
@@ -1915,7 +1915,7 @@
 			foreach ($arCalculation['product'] as $product_index => $p) {
 				
-				$arReturn['produkte'][$product_index]['preis'] = (($this->shop->getFrontendTaxview() === WPSG_NETTO)?$p['netto']:$p['brutto']);
-				$arReturn['produkte'][$product_index]['preis_netto'] = $p['netto'];
-				$arReturn['produkte'][$product_index]['preis_brutto'] = $p['brutto'];
+				$arReturn['produkte'][$product_index]['preis'] = (($this->shop->getFrontendTaxview() === WPSG_NETTO)?$p['netto_single']:$p['brutto_single']);
+				$arReturn['produkte'][$product_index]['preis_netto'] = $p['netto_single'];
+				$arReturn['produkte'][$product_index]['preis_brutto'] = $p['brutto_single'];
 				
 			}
Index: /lib/wpsg_calculation.class.php
===================================================================
--- /lib/wpsg_calculation.class.php	(revision 7250)
+++ /lib/wpsg_calculation.class.php	(revision 7251)
@@ -260,5 +260,5 @@
 			} 
 			
-            if ($product_index === false) $product_index = $this->getMaxProductIndex();
+            if ($product_index === false) $product_index = $this->getMaxProductIndex() + 1;
             
             if (wpsg_isSizedInt($order_product_id)) {