diff --git a/library/HTMLPurifier/DefinitionCache/Serializer.php b/library/HTMLPurifier/DefinitionCache/Serializer.php
index ecacb88f..ce268d91 100644
--- a/library/HTMLPurifier/DefinitionCache/Serializer.php
+++ b/library/HTMLPurifier/DefinitionCache/Serializer.php
@@ -219,9 +219,15 @@ class HTMLPurifier_DefinitionCache_Serializer extends HTMLPurifier_DefinitionCac
             } elseif (!$this->_testPermissions($base, $chmod)) {
                 return false;
             }
-            $old = umask(0000);
             mkdir($directory, $chmod);
-            umask($old);
+            if (!$this->_testPermissions($directory, $chmod)) {
+                trigger_error(
+                    'Base directory ' . $base . ' does not exist,
+                    please create or change using %Cache.SerializerPath',
+                    E_USER_WARNING
+                );
+                return false;
+            }
         } elseif (!$this->_testPermissions($directory, $chmod)) {
             return false;
         }
diff --git a/tests/HTMLPurifier/DefinitionCache/SerializerTest.php b/tests/HTMLPurifier/DefinitionCache/SerializerTest.php
index badf9d98..3af8c12f 100644
--- a/tests/HTMLPurifier/DefinitionCache/SerializerTest.php
+++ b/tests/HTMLPurifier/DefinitionCache/SerializerTest.php
@@ -211,14 +211,14 @@ class HTMLPurifier_DefinitionCache_SerializerTest extends HTMLPurifier_Definitio
         $config->setReturnValue('get', 1, array('Test.DefinitionRev'));
         $dir = dirname(__FILE__) . '/SerializerTest';
         $config->setReturnValue('get', $dir, array('Cache.SerializerPath'));
-        $config->setReturnValue('get', 0777, array('Cache.SerializerPermissions'));
+        $config->setReturnValue('get', 0700, array('Cache.SerializerPermissions'));
 
         $def_original = $this->generateDefinition();
         $cache->add($def_original, $config);
         $this->assertFileExist($dir . '/Test/1.0.0,serial,1.ser');
 
-        $this->assertEqual(0666, 0777 & fileperms($dir . '/Test/1.0.0,serial,1.ser'));
-        $this->assertEqual(0777, 0777 & fileperms($dir . '/Test'));
+        $this->assertEqual(0600, 0777 & fileperms($dir . '/Test/1.0.0,serial,1.ser'));
+        $this->assertEqual(0700, 0777 & fileperms($dir . '/Test'));
 
         unlink($dir . '/Test/1.0.0,serial,1.ser');
         rmdir( $dir . '/Test');