[CentOS] mount cdrom and command hangs

Hi

I had accidentally did "mount /media/cdrom" and no cd was present.
The command seems to be hung.
I tried kill and kill -9 on the mount command.
Nothing seems to kill it.

Is there anything else to try to stop that command?
I'm on centos 4.1

as an asside is there a command that "senses" if there is a CDROM
present in the tray so I dount have to mount /media/cdrom and it fail
to tell if a cdrom is present.

jerry