Congratulations! You broke it!

You are in debug mode. Your session will not be destroyed ;-)
Zend_Log_Exception: "/home/sklepsakralny/public_html/production/environment/logs/core-error.log.txt" cannot be opened with mode "a"
thrown in /libraries/Zend/Log/Writer/Stream.php:81

 [0] Zend_Log_Writer_Stream->__construct() called at /application/core/System/Bootstrap.php:680
 [1] System_Bootstrap->setLogs() called at /application/core/InitBoot.php:225
 [2] require() called at /index.php:69