3 files changed, 14 insertions, 1 deletions
diff --git a/activesupport/CHANGELOG b/activesupport/CHANGELOG
index ff9cd4d979..e1b4b9a516 100644
--- a/activesupport/CHANGELOG
+++ b/activesupport/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* TimeWithZone#usec returns 0 instead of error when DateTime is wrapped [Geoff Buesing]
+
 * Improve documentation. [Radar, Jan De Poorter, chuyeow, xaviershay, danger, miloops, Xavier Noria,  Sunny Ripert]
 
 * Ensure that TimeWithZone#to_yaml works when passed a YAML::Emitter.  [rick]
diff --git a/activesupport/lib/active_support/time_with_zone.rb b/activesupport/lib/active_support/time_with_zone.rb
index 56c4f40f32..3c37ab2d4c 100644
--- a/activesupport/lib/active_support/time_with_zone.rb
+++ b/activesupport/lib/active_support/time_with_zone.rb
@@ -143,7 +143,7 @@ module ActiveSupport
       end
     end
     
-    %w(asctime day hour min mon sec usec wday yday year to_date).each do |name|
+    %w(asctime day hour min mon sec wday yday year to_date).each do |name|
       define_method(name) do
         time.__send__(name)
       end
@@ -152,6 +152,10 @@ module ActiveSupport
     alias_method :mday, :day
     alias_method :month, :mon
     
+    def usec
+      time.respond_to?(:usec) ? time.usec : 0
+    end
+    
     %w(sunday? monday? tuesday? wednesday? thursday? friday? saturday?).each do |name|
       define_method(name) do
         time.__send__(name)
diff --git a/activesupport/test/core_ext/time_with_zone_test.rb b/activesupport/test/core_ext/time_with_zone_test.rb
index 70b3d90bd6..4fe1be3ed6 100644
--- a/activesupport/test/core_ext/time_with_zone_test.rb
+++ b/activesupport/test/core_ext/time_with_zone_test.rb
@@ -326,6 +326,13 @@ uses_tzinfo 'TimeWithZoneTest' do
       end
     end
     
+    def test_usec_returns_0_when_datetime_is_wrapped
+      silence_warnings do # silence warnings raised by tzinfo gem
+        twz = ActiveSupport::TimeWithZone.new(DateTime.civil(2000), @time_zone)
+        assert_equal 0, twz.usec
+      end
+    end
+    
     def test_utc_to_local_conversion_saves_period_in_instance_variable
       silence_warnings do # silence warnings raised by tzinfo gem
         assert_nil @twz.instance_variable_get('@period')