Conform to ActiveSupport::Cache#delete's interface in Memcached::Rails.

lib/memcached/rails.rb

@@ -76,8 +76,8 @@ class Memcached
     end
 
     # Wraps Memcached#delete so that it doesn't raise.
-    def delete(key)
-      super
+    def delete(key, expiry=0)
+      super(key)
     rescue NotFound
     end
 

test/unit/rails_test.rb

@@ -41,6 +41,13 @@ class RailsTest < Test::Unit::TestCase
     end
   end
 
+  def test_delete_with_two_arguments
+    assert_nothing_raised do
+      @cache.delete(key, 5)
+      assert_nil(@cache.get(key))
+    end
+  end
+
   def test_bracket_accessors
     @cache[key] = @value
     result = @cache[key]