Using perl to change the loginwindow.plist

[Greg Kapp]

I'm trying to use perl to change plist files. My goal is to change the loginwindow.plist file of every user on the machine I administer. I want to change the plist to add a text file that will be opened apon login (this will serve as a sort-of message of the day file).

Does anyone have any information about writing plists in general or the loginwindow.plist specifically. I haven't seen anything that makes the XML format clear, indicating which fields are required and which are not.

Thanks-
Greg