fixing paypal ipn received_at time parsing

lib/active_merchant/billing/integrations/paypal/notification.rb

@@ -54,7 +54,8 @@ def complete?
           # One possible scenario is that our web application was down. In this case paypal tries several 
           # times an hour to inform us about the notification
           def received_at
-            Time.parse params['payment_date']
+            parsed_time_fields = DateTime._strptime(params['payment_date'], "%H:%M:%S %b %d, %Y %z")
+            Time.mktime(*parsed_time_fields.values_at(:year, :mon, :mday, :hour, :min, :sec, :zone))
           end
 
           # Status of transaction. List of possible values:

test/unit/integrations/notifications/paypal_notification_test.rb

@@ -76,6 +76,11 @@ def test_nil_notification
     Paypal::Notification.any_instance.stubs(:ssl_post).returns('INVALID')
     assert !@paypal.acknowledge
   end
+
+  def test_received_at_time_parsing
+    paid_at = "15/04/2005 15:23:54 -0400"
+    assert_equal paid_at, @paypal.received_at.strftime("%d/%m/%Y %H:%M:%S %z")
+  end
 
   private