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

Call Stack:
    0.0019     236816   1. {main}() /home/gongquiz_blog/www/index.php:0
    7.1001     238104   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    7.1007     272272   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    7.1307    1142816   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    7.1309    1159264   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    7.1323    1353824   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    7.1324    1355568   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81