Trying to script an OD archive

I'm attempting to script an automated OD archive using the methods outlined on page 238 of the Mac OS X Directory Services 10.6 book from Peachpit Press.

The first step is to create a file called archiveODM.commands with the following:

dirserv:backupArchiveParams:archivePassword = <password>
dirserv:backupArchiveParams:archivePath = /Volumes/Server\ HD3/ODarchive
dirserv:command = backupArchive

Then create the archiveODM.sh file with the following:

#!/bin/sh
/usr/sbin/serveradmin command < /Users/sadmin/archiveODM.commands

When I run the archiveODM.sh command, I get the following error:

enterprise:Desktop sadmin$ sudo sh /Users/sadmin/archiveODM.sh
2011-07-11 14:26:37.835 serveradmin[32391:903] --Module NSBundle </usr/share/servermgrd/bundles/servermgr_dirserv.bundle> (loaded)'s response has retain count of 3.
dirserv = _empty_dictionary

I'm not really sure where to go from here.