diff --git a/lib/fog/rackspace/requests/monitoring/update_entity.rb b/lib/fog/rackspace/requests/monitoring/update_entity.rb
index 46303ac5f..5eaa1e97d 100644
--- a/lib/fog/rackspace/requests/monitoring/update_entity.rb
+++ b/lib/fog/rackspace/requests/monitoring/update_entity.rb
@@ -3,15 +3,44 @@ module Fog
     class Monitoring
       class Real
 
-        def update_entity(id, options)
+        def update_entity(entity_id, options)
           request(
             :body     => JSON.encode(options),
             :expects  => [204],
             :method   => 'PUT',
-            :path     => "entities/#{id}"
+            :path     => "entities/#{entity_id}"
           )
         end
       end
+
+      class Mock
+
+        def update_entity(entity_id, options)
+
+          if entity_id == -1
+           raise Fog::Rackspace::Monitoring::NotFound
+          end
+
+          response = Excon::Response.new
+          response.status = 204
+          response.body = ""
+          response.headers = {
+            "Date"                  => Time.now.utc.to_s,
+            "Location"              => "https://monitoring.api.rackspacecloud.com/v1.0/55555/entities/" + entity_id.to_s,
+            "X-Object-ID"           => entity_id.to_s,
+            "X-RateLimit-Limit"     => "50000",
+            "X-RateLimit-Remaining" => "47877",
+            "X-RateLimit-Window"    => "24 hours",
+            "X-RateLimit-Type"      => "global",
+            "X-Response-Id"         => "lakbngf9bsgkn69gb39sobnsv",
+            "X-LB"                  => "dfw1-maas-prod-api1",
+            "Content-Length"        => "0",
+            "Content-Type"          => "text/plain"
+          }
+          response.remote_ip = "1.1.1.1"
+          response
+        end
+      end 
     end
   end
 end
diff --git a/tests/rackspace/requests/monitoring/entity_tests.rb b/tests/rackspace/requests/monitoring/entity_tests.rb
index 6f76a9a3e..50fd2b87b 100644
--- a/tests/rackspace/requests/monitoring/entity_tests.rb
+++ b/tests/rackspace/requests/monitoring/entity_tests.rb
@@ -12,8 +12,7 @@ Shindo.tests('Fog::Rackspace::Monitoring | entity_tests', ['rackspace','rackspac
       account.get_entity(:entity_id => "fooid")
     end
     tests('#update entity').formats(DATA_FORMAT) do
-      pending if Fog.mocking? 
-      options = { :testing => "Bar"}
+      options = { :metadata => {:testing => "Bar" }}
       account.update_entity(entity_id,options).data
     end
     tests('#delete entity').formats(DELETE_DATA_FORMAT) do
@@ -28,8 +27,7 @@ Shindo.tests('Fog::Rackspace::Monitoring | entity_tests', ['rackspace','rackspac
       account.get_entity(-1)
     end
     tests('#update invalid entity(-1)').raises(Fog::Rackspace::Monitoring::NotFound) do
-      pending if Fog.mocking? 
-      options = { :testing => "Bar" }
+      options = { :metadata => {:testing => "Bar" }}
       response = account.update_entity(-1,options)
     end
     tests('#delete entity(-1)').raises(Fog::Rackspace::Monitoring::NotFound) do