oracle em的问题。。

[长烟慢慢]

我执行了这个emctl start dbconsole 操作，这是什么意思啊？ invalid argument 怎么回事？会影响进入em吗？？
C:\Documents and Settings\Administrator>emctl start dbconsole;
Oracle Enterprise Manager 10g Database Control Release 10.1.0.2.0
Copyright (c) 1996, 2004 Oracle Corporation. All rights reserved.
Invalid arguments

Unknown command option start
Usage::
Oracle Enterprise Manager 10g Database Control commands:
emctl start| stop| status dbconsole
emctl secure <options>

emctl set ssl test|off|on em
emctl set ldap <host> <port> <user dn> <user pwd> <context dn>
emctl blackout options can be listed by typing "emctl blackout"
emctl config options can be listed by typing "emctl config"
emctl secure options can be listed by typing "emctl secure"
emctl ilint options can be listed by typing "emctl ilint"
emctl deploy options can be listed by typing "emctl deploy"