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

Call Stack:
    0.0349     234400   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.5296     235688   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    1.1308     270272   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    4.7716    1142840   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    4.7718    1159272   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    4.7736    1353896   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    4.7738    1355648   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81