Hi ,
I removed tthe older version of MediaWiki 1.13 and installed Mediawiki 1.25. I completed all the config changes and ran update.php and it ran fine for the first time. But now i get an exception Invalid callback MyExtensionHooks::onLogException in hooks for LogException and the following error in debug_log
#0 /apps/Mediawiki/includes/exception/MWExceptionHandler.php(522): Hooks::run('LogException', Array)
#1 /apps/Mediawiki/includes/exception/MWExceptionHandler.php(222): MWExceptionHandler::logError(Object(ErrorException), 'error')
#2 [internal function]: MWExceptionHandler::handleError(2, 'date_default_ti...', '/apps/htdocs/wi...', 546, Array)
#3 /apps/Mediawiki/includes/Setup.php(546): date_default_timezone_get()
#4 /apps/Mediawiki/maintenance/doMaintenance.php(97): require_once('/apps/htdocs/wi...')
#5 /apps/Mediawiki/maintenance/update.php(216): require_once('/apps/htdocs/wi...')
#6 {main}
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