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

Call Stack:
    3.5220     235760   1. {main}() /home/gongquiz_blog/www/index.php:0
    3.5222     237048   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    3.5226     271216   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    5.7958    1141856   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    5.7966    1158304   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    5.7996    1352816   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    5.7997    1354544   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81