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

Call Stack:
    0.0001     231472   1. {main}() /home/gongquiz_blog/www/index.php:0
    3.0890     232760   2. require('/home/gongquiz_blog/www/_common.php') /home/gongquiz_blog/www/index.php:2
    3.0895     267344   3. include_once('/home/gongquiz_blog/lib/common.php') /home/gongquiz_blog/www/_common.php:3
    4.6816    1140160   4. dbConn->__construct() /home/gongquiz_blog/lib/common.php:68
    4.6818    1156584   5. log_e() /home/gongquiz_blog/lib/common/dbConn.class.php:48
    4.6873    1349672   6. error_::log_e() /home/gongquiz_blog/lib/libf.php:564
    4.6874    1351384   7. error_::log() /home/gongquiz_blog/lib/common/error_.class.php:81