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

Call Stack:
    0.0001     235936   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.0001     237224   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    0.0004     271392   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    3.0808    1142080   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    3.0814    1158488   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    3.0849    1352984   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    3.0853    1354704   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81