Fatal error @ http://conference.postgresql.org/

I see PHP's fatal error message at http://conference.postgresql.org/:

***
Fatal error: Access level to TFramewerk::__construct() must be
protected (as in class TFramewerkSingletonObject) or weaker in
/home/josh/websites/conference.postgresql.org/Include/TFramewerk.inc
on line 46
***

BTW, what about display_errors=Off in php.ini? It's always better to
keep log_errors=On and display_errors=Off in production environment.

-- 
Best regards,
Nikolay