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

Call Stack:
    0.0001     232840   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.0002     234128   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    0.1051     268712   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    1.5596    1141360   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    1.5598    1157784   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    1.5632    1352432   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    1.5633    1354168   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81