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

Call Stack:
    0.0557     233080   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.0558     234368   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    1.1015     268952   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    1.2011    1141488   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    1.2119    1157936   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    1.6069    1351008   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:564
    1.6071    1352720   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81