Same problem here.
Joomla 3.2, JoomSEF installed, but when manage SEF URLs, page went blank.

Frontend and backend are both blank. Could not get niether to admin panel.

ERROR: Fatal error: Cannot access property started with '\0' in /domains/mojapot.net/public_html/libraries/joomla/registry/registry.php on line 439


PAGE: www.mojapot.net