woothemes / woocommerce

				$item_taxes = WC_Tax::calc_shipping_tax( $amount, WC_Tax::get_shipping_tax_rates( $cart[ $cost_key ]['data']->get_tax_class() ) );

				// Sum the item taxes

				foreach ( array_keys( $taxes + $item_taxes ) as $key ) {

					$taxes[ $key ] = ( isset( $item_taxes[ $key ] ) ? $item_taxes[ $key ] : 0 ) + ( isset( $taxes[ $key ] ) ? $taxes[ $key ] : 0 );

				}

			}

			// Add any cost for the order - order costs are in the key 'order'

				$item_taxes = WC_Tax::calc_shipping_tax( $costs['order'], WC_Tax::get_shipping_tax_rates() );

				// Sum the item taxes

				foreach ( array_keys( $taxes + $item_taxes ) as $key ) {

					$taxes[ $key ] = ( isset( $item_taxes[ $key ] ) ? $item_taxes[ $key ] : 0 ) + ( isset( $taxes[ $key ] ) ? $taxes[ $key ] : 0 );

				}

			}

		}