Creating device files in /dev

I'm running Freebsd 5.1and I'm unable to create a device file or pipe
file in the /dev directory.

/dev is a devfs file system which seems to be the problem.

Is there any way around this?  Either by adding an entry to a
kernel config file or using the devfs command to create them?

I have a backup program that needs to create a device file and pipe
file that reside in /dev  This is a must for my backups and recovery.


Thank You