diff -rupN uc_discounts_alt_org//uc_discounts/uc_discounts.module uc_discounts_alt//uc_discounts/uc_discounts.module
--- uc_discounts_alt_org//uc_discounts/uc_discounts.module	2011-09-27 18:07:32.000000000 +0200
+++ uc_discounts_alt//uc_discounts/uc_discounts.module	2011-11-02 09:56:51.000000000 +0100
@@ -1771,7 +1771,7 @@ function get_discounts_for_order($order,
     }
 
     //Round the discount to two places
-    $discount->amount = round($discount->amount, 2);
+    $discount->amount = round(floatval($discount->amount.' '), 2);
 
     //Add this discount's amount to running total
     $total_discount_amount += $discount->amount;