Fatal error: Class 'Client' not found in /home/gongquiz_blog/lib/common/error_.class.php on line 92

Call Stack:
    2.6588     238200   1. {main}() /home/gongquiz_blog/www/index.php:0
    2.6588     239488   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    2.6591     273656   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    2.6664    1144432   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    2.6665    1160824   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    2.6679    1355368   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    2.6680    1357088   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81