一台机器运行2个不同版本的库，安装失败

描述下问题的情况：

由于已经安装了5.0版本的mysql；现在想使用mysql2用户，安装mysql6.0的版本

报错如下：

高手看看啥情况

mysql_install_db --user=mysql2

Installing MySQL system tables...

2015-12-11 15:41:54 0 [Warning] Using unique option prefix pid instead of pid_file is deprecated and will be removed in a future release. Please use the full name instead.

2015-12-11 15:41:54 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).

2015-12-11 15:41:54 19417 [Note] Plugin 'InnoDB' is disabled.

2015-12-11 15:41:54 19417 [Note] Plugin 'FEDERATED' is disabled.

2015-12-11 15:41:54 19417 [ERROR] /home/mysql2/mysql/bin/mysqld: unknown option '--skip-bdb'

2015-12-11 15:41:54 19417 [ERROR] Aborting

2015-12-11 15:41:54 19417 [Note] Binlog end

2015-12-11 15:41:54 19417 [Note] /home/mysql2/mysql/bin/mysqld: Shutdown complete

Installation of system tables failed!