当访问：http://12.34.56.78/mail/时，显示：
SERVICE CURRENTLY NOT AVAILABLE!

Error No. [500]

maillog日志显示：

Jun  7 08:26:38 mail roundcube: [07-Jun-2010 08:26:38 -0400]: DB Error: _doQuery: [Error message: Could not execute statement] [Last executed query: PREPARE mdb2_statement_mysqli
_1680d85c4cdf7f6b5820dfeaef67a95af5bcbc6c2 FROM 'SELECT vars, ip, UNIX_TIMESTAMP(changed) AS changed\n     FROM session\n     WHERE  sess_id=?'] [Native code: 1146] [Native messa
ge: Table 'roundcubemail.session' doesn't exist]  in /var/www/roundcubemail-0.3.1/program/include/rcube_mdb2.php on line 269 (GET /mail/)
Jun  7 08:26:46 mail roundcube: MDB2 Error: no such table (-18): _doQuery: [Error message: Could not execute statement] [Last executed query: PREPARE mdb2_statement_mysqli_1b69ab
6ea660714f1259dd729973624369278d46d FROM 'SELECT vars, ip, UNIX_TIMESTAMP(changed) AS changed\n     FROM session\n     WHERE  sess_id=?'] [Native code: 1146] [Native message: Tab
le 'roundcubemail.session' doesn't exist]
Jun  7 08:26:46 mail roundcube: [07-Jun-2010 08:26:46 -0400]: DB Error: _doQuery: [Error message: Could not execute statement] [Last executed query: PREPARE mdb2_statement_mysqli
_1b69ab6ea660714f1259dd729973624369278d46d FROM 'SELECT vars, ip, UNIX_TIMESTAMP(changed) AS changed\n     FROM session\n     WHERE  sess_id=?'] [Native code: 1146] [Native messa
ge: Table 'roundcubemail.session' doesn't exist]  in /var/www/roundcubemail-0.3.1/program/include/rcube_mdb2.php on line 269 (GET /mail/index.php)
Jun  7 08:27:01 mail roundcube: MDB2 Error: no such table (-18): _doQuery: [Error message: Could not execute statement] [Last executed query: PREPARE mdb2_statement_mysqli_1e82da
82753924d62c7443b706e3567460f8fa713 FROM 'SELECT vars, ip, UNIX_TIMESTAMP(changed) AS changed\n     FROM session\n     WHERE  sess_id=?'] [Native code: 1146] [Native message: Tab
le 'roundcubemail.session' doesn't exist]

提示：roundcubemail.session' doesn't exist   这里应该如何处理？

经我测试，邮件系统可以正常收发邮件，只有这里出错。我用的是0.6.0版本