http://railsdog.lighthouseapp.com/projects/31096-spree/tickets/1788

unavailable-shipping-methods-should-not-be-free.patch

commit 1a448022d42dd91021b042ecb7d31f60170352e5
Author: Sam Beam <sbeam@onsetcorps.net>
Date:   Mon Dec 6 21:08:43 2010 -0500

    return a nil from Calculator::ActiveShipping::compute when the method is not found in the API response, and pass it through so the customer is not presented with a free shipping option

diff --git a/app/controllers/checkouts_controller.rb b/app/controllers/checkouts_controller.rb
index 1b94dc2..7c56f8d 100644
--- a/app/controllers/checkouts_controller.rb
+++ b/app/controllers/checkouts_controller.rb
@@ -225,7 +225,7 @@ class CheckoutsController < Spree::BaseController
           :name => ship_method.name,
           :cost => ship_method.calculate_cost(@checkout.shipment)
         }
-      end.sort_by{|r| r[:cost]}
+      end.reject{ |r| r[:cost].nil? }.sort_by{|r| r[:cost]}
     rescue Spree::ShippingError => ship_error
       flash[:error] = ship_error.to_s
       []
diff --git a/app/models/shipping_method.rb b/app/models/shipping_method.rb
index ada66fc..f3f1b11 100644
--- a/app/models/shipping_method.rb
+++ b/app/models/shipping_method.rb
@@ -17,9 +17,9 @@ class ShippingMethod < ActiveRecord::Base
     }.map{ |shipping_category_id, line_items|
       calc = rate_calculators[shipping_category_id] || self.calculator
       calc.compute(line_items)
-    }.sum
+    }.reject(&:nil?)
 
-    return(calculated_costs)
+    return calculated_costs.sum unless calculated_costs.blank?
   end
 
   def available?(order, display_on=nil)
diff --git a/vendor/extensions/active_shipping/app/models/calculator/active_shipping.rb b/vendor/extensions/active_shipping/app/models/calculator/active_shipping.rb
index 06ac2a5..df4452e 100644
--- a/vendor/extensions/active_shipping/app/models/calculator/active_shipping.rb
+++ b/vendor/extensions/active_shipping/app/models/calculator/active_shipping.rb
@@ -28,7 +28,7 @@ class Calculator::ActiveShipping < Calculator
       rates = retrieve_rates(origin, destination, packages(order))
     end
 
-    return nil if rates.empty?
+    return nil if rates.empty? or rates[self.description].nil?
     rate = rates[self.description].to_f + (Spree::ActiveShipping::Config[:handling_fee].to_f || 0.0)
     return nil unless rate
     # divide by 100 since active_shipping rates are expressed as cents