на сайте возникли сообщения об ошибки

на сайте возникли сообщения об ошибки
Warning: strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Asia/Samarkand' for 'UZT/5.0/no DST' instead in /home/vsemirna/public_html/libraries/joomla/utilities/date.php on line 56

Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Asia/Samarkand' for 'UZT/5.0/no DST' instead in /home/vsemirna/public_html/libraries/joomla/utilities/date.php on line 198

Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Asia/Samarkand' for 'UZT/5.0/no DST' instead in /home/vsemirna/public_html/libraries/joomla/utilities/date.php on line 198

 

Добрый день. Помогите исправить!
На моем сайте в модуле "Обновления" появились сообщения: Warning: Creating default object from empty value in /home/slovarax/public_html/modules/mod_latestnews/helper.php on line 109.

И также в Менеджере материалов: Warning: Creating default object from empty value in /home/slovarax/public_html/administrator/components/com_content/controller.php on line 96.
Кто знает как исправить?