There are several problems updating a moodle install from from moodle-2.1.10-1.el6.noarch to moodle-2.2.9-1.el6.noarch (or 2.2.7-1.el6)

Updating the RPM fails with the error
error: unpacking of archive failed on file /var/www/moodle/web/lib/pear/HTML/QuickForm: cpio: rename

and if you manually delete /var/www/moodle/web/lib/pear/HTML/QuickForm first (so it can create the symlink) you get the similar error

error: unpacking of archive failed on file /var/www/moodle/web/lib/pear/OLE: cpio: rename

If you likewise work around this then upgrading the data gets as far as the 
Course overview plugin and then quits with the error (when debugging is turned on)

Warning: require_once(HTML/QuickForm/DHTMLRulesTableless.php): failed to open stream: No such file or directory in /var/www/moodle/web/lib/formslib.php on line 44 Fatal error: require_once(): Failed opening required 'HTML/QuickForm/DHTMLRulesTableless.php' (include_path='/var/www/moodle/web/lib/zend:/var/www/moodle/web/lib/pear:.:/usr/share/pear:/usr/share/php') in /var/www/moodle/web/lib/formslib.php on line 44

so the php-pear-HTML-QuickForm package is missing DHTMLRulesTableless.php (also Renderer/Tableless.php) which moodle uses.