Editing System/Library files with Property List Editor (PLE) I want to update the schedule in /System/Library/LaunchDaemons/com.apple.locate.plist.  I have unlocked the file in Finder but the Property List Editor is giving me:


The file "com.apple.locate.plist" could not be unlocked.

Could not add write permission to the file because you do not own it.  Try modifying the permissions of the file in the Finder or Terminal.


I don't want to make myself the owner of a System file.  Is there a way to edit this file without manually changing the permissions?
Couldn't you just use a code editor? At least TextMate and TextWrangler can convert property lists from binary to XML and authentificate as root in order to save files.