1 files changed, 16 insertions, 2 deletions
diff --git a/actionpack/lib/action_controller/routing/segments.rb b/actionpack/lib/action_controller/routing/segments.rb
index efac2df1cb..24ea8c7f2d 100644
--- a/actionpack/lib/action_controller/routing/segments.rb
+++ b/actionpack/lib/action_controller/routing/segments.rb
@@ -171,10 +171,19 @@ module ActionController
       end
 
       def value_regexp
-        Regexp.new "\\A#{regexp.source}\\Z" if regexp
+        Regexp.new "\\A#{regexp.to_s}\\Z" if regexp
       end
+
       def regexp_chunk
-        regexp ? "(#{regexp.source})" : "([^#{Routing::SEPARATORS.join}]+)"
+        if regexp 
+          if regexp_has_modifiers?
+            "(#{regexp.to_s})"
+          else
+            "(#{regexp.source})"
+          end
+        else
+          "([^#{Routing::SEPARATORS.join}]+)"
+        end
       end
 
       def build_pattern(pattern)
@@ -183,6 +192,7 @@ module ActionController
         pattern = "#{chunk}#{pattern}"
         optional? ? Regexp.optionalize(pattern) : pattern
       end
+
       def match_extraction(next_capture)
         # All non code-related keys (such as :id, :slug) are URI-unescaped as
         # path parameters.
@@ -201,6 +211,10 @@ module ActionController
         [:action, :id].include? key
       end
 
+      def regexp_has_modifiers?
+        regexp.options & (Regexp::IGNORECASE | Regexp::EXTENDED) != 0
+      end
+
     end
 
     class ControllerSegment < DynamicSegment #:nodoc: