I'm not sure you'll be able to even do that with defaults. The
defaults man page says:
"BUGS
Defaults can be structured in very complex ways, making it
difficult for the user to enter them with this command."
That is a perfect candidate for PlistBuddy, another plist modifier
that works from the command line. In OS X Leopard PlistBuddy is
included (/usr/libexec), but in previous versions you would have to
find in in a package receipt or something. There is a bit of
documentation about this on the web.
In our Tiger base image, I copy PlistBuddy to /usr/bin so that I know
it will always be in the path; now that we are using Leopard this is
unnecessary.
Ryan Harter
UW - Stevens Point
Workstation Developer
715.346.2716
Ryan.Harter at uwsp.edu