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

Call Stack:
    0.0016     235808   1. {main}() /home/gongquiz_blog/www/index.php:0
    0.0016     237096   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    0.0052     271264   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    1.1321    1141904   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    1.1332    1158352   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    1.8369    1352880   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:563
    1.9077    1354608   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81