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

Call Stack:
    0.3506     237160   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.3519     238448   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    0.3543     272616   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    0.7708    1143360   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    0.7710    1159792   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    0.8767    1354288   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    0.8768    1356016   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81