diff --git a/lib/fog/rackspace/requests/monitoring/update_alarm.rb b/lib/fog/rackspace/requests/monitoring/update_alarm.rb
index a4348e57a..950cc3e3e 100644
--- a/lib/fog/rackspace/requests/monitoring/update_alarm.rb
+++ b/lib/fog/rackspace/requests/monitoring/update_alarm.rb
@@ -3,15 +3,46 @@ module Fog
     class Monitoring
       class Real
 
-        def update_alarm(entity_id, id, options)
+        def update_alarm(entity_id, alarm_id, options)
           request(
             :body     => JSON.encode(options),
             :expects  => [204],
             :method   => 'PUT',
-            :path     => "entities/#{entity_id}/alarms/#{id}"
+            :path     => "entities/#{entity_id}/alarms/#{alarm_id}"
           )
         end
       end
+
+      class Mock
+
+        def update_alarm(entity_id, alarm_id, options)
+
+          account_id = Fog::Mock.random_numbers(6).to_s
+
+          if entity_id == -1 || alarm_id == -1 || options[:testing]
+            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/" + account_id + "/entities/" + entity_id.to_s + "/alarms/" + alarm_id,
+            "X-Object-ID"           => alarm_id,
+            "X-RateLimit-Limit"     => "50000",
+            "X-RateLimit-Remaining" => "47877",
+            "X-RateLimit-Window"    => "24 hours",
+            "X-RateLimit-Type"      => "global",
+            "X-Response-Id"         => "laolsgggopsnfksdovnsv",
+            "X-LB"                  => "dfw1-maas-prod-api1",
+            "Content-Length"        => "0",
+            "Content-Type"          => "text/plain"
+          }
+          response.remote_ip = Fog::Rackspace::MockData.ipv4_address
+          response
+        end
+      end
     end
   end
 end
diff --git a/tests/rackspace/requests/monitoring/alarm_tests.rb b/tests/rackspace/requests/monitoring/alarm_tests.rb
index 17c18e9a9..d5bcc6710 100644
--- a/tests/rackspace/requests/monitoring/alarm_tests.rb
+++ b/tests/rackspace/requests/monitoring/alarm_tests.rb
@@ -19,7 +19,6 @@ Shindo.tests('Fog::Rackspace::Monitoring | alarm_tests', ['rackspace','rackspace
       response
     end
     tests('#update alarm').formats(DATA_FORMAT) do
-      pending if Fog.mocking?
       options = { :label => "Bar"}
       account.update_alarm(entity_id,alarm_id,options).data
     end
@@ -39,7 +38,6 @@ Shindo.tests('Fog::Rackspace::Monitoring | alarm_tests', ['rackspace','rackspace
       account.create_alarm(entity_id, {:type => ""})
     end
     tests('#fail to update invalid alarm(-1)').raises(Fog::Rackspace::Monitoring::NotFound) do
-      pending if Fog.mocking?
       options = { :testing => "Bar" }
       response = account.update_alarm(-1,-1,options)
     end