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

Call Stack:
    0.0002     237304   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.0002     238592   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    0.0042     272760   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    0.0384    1143296   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    0.0425    1159720   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    1.1713    1354264   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    1.1715    1356008   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81