Workaround for:

 https://bugzilla.redhat.com/show_bug.cgi?id=747361

--- REST.php.restcache

+++ REST.php

@@ -234,6 +234,13 @@

             }

         }

+        if (!is_writeable($cache_dir)) {

+            // If writing to the cache dir is not going to work, silently do nothing.

+            // An ugly hack, but retains compat with PEAR 1.9.1 where many commands

+            // work fine as non-root user (w/out write access to default cache dir).

+            return true;

+        }

+

         if ($cacheid === null && $nochange) {

             $cacheid = unserialize(implode('', file($cacheidfile)));

         }