diff --git a/cache/stores/memcached/addinstanceform.php b/cache/stores/memcached/addinstanceform.php
index a8e98bf0f48..293b1988153 100644
--- a/cache/stores/memcached/addinstanceform.php
+++ b/cache/stores/memcached/addinstanceform.php
@@ -57,7 +57,7 @@ class cachestore_memcached_addinstance_form extends cachestore_addinstance_form
         $form->addElement('select', 'serialiser', get_string('useserialiser', 'cachestore_memcached'), $serialiseroptions);
         $form->addHelpButton('serialiser', 'useserialiser', 'cachestore_memcached');
         $form->setDefault('serialiser', Memcached::SERIALIZER_PHP);
-        $form->setType('serialiser', PARAM_NUMBER);
+        $form->setType('serialiser', PARAM_INT);
 
         $form->addElement('text', 'prefix', get_string('prefix', 'cachestore_memcached'), array('size' => 16));
         $form->setType('prefix', PARAM_ALPHANUM);
@@ -74,4 +74,4 @@ class cachestore_memcached_addinstance_form extends cachestore_addinstance_form
         $form->setDefault('bufferwrites', 0);
         $form->setType('bufferwrites', PARAM_BOOL);
     }
-}
\ No newline at end of file
+}
diff --git a/cache/stores/memcached/lib.php b/cache/stores/memcached/lib.php
index 6e3834cce0f..4f96fda5f14 100644
--- a/cache/stores/memcached/lib.php
+++ b/cache/stores/memcached/lib.php
@@ -339,7 +339,7 @@ class cachestore_memcached extends cache_store implements cache_is_configurable
             $options[Memcached::SERIALIZER_JSON] = get_string('serialiser_json', 'cachestore_memcached');
         }
         if (Memcached::HAVE_IGBINARY) {
-            $options[Memcached::SERIALIZER_IGBINARY] = get_string('serialiser_php', 'cachestore_memcached');
+            $options[Memcached::SERIALIZER_IGBINARY] = get_string('serialiser_igbinary', 'cachestore_memcached');
         }
         return $options;
     }