innodb引擎Plugin 'InnoDB' registration as a STORAGE ENGINE failed.

今天在做innodb参数配置的时候，对其默认配置加以修改--结果导致启动后的server竟然不支持innodb引擎。Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
错误日志：
InnoDB: Data file /usr/local/mysql4/data/ibdata2 did not exist: new to be created
100702 14:34:53 InnoDB: Setting file /usr/local/mysql4/data/ibdata2 size to 20 MB
InnoDB: Database physically writes the file full: wait...
InnoDB: No valid checkpoint found.
InnoDB: If this error appears when you are creating an InnoDB database,
InnoDB: the problem may be that during an earlier attempt you managed
InnoDB: to create the InnoDB data files, but log file creation failed.
InnoDB: If that is the case, please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.1/en/error-creating-innodb.html
100702 14:34:54 [ERROR] Plugin 'InnoDB' init function returned error.
100702 14:34:54 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
在遇到这些情况的时候，我起初考虑是没有建立新日志文件的权限。
实则不然
当我在未正常关闭server的情况下对其参数修改，
修改之后没有删除ib_logfile文件，ib_logfile文件中记录些innodb引擎非常有用的信息比如说默认的innodb默认的配置信息，你又是在未正常关闭server情况下操作的，所以导致重启后的server不支持innodb引擎。
rm -rf ib_logfile*
正确配置参数
重启server。