When opening a printer in the "Printer Selector" window, the current printer zone selected remains constant throughout ANY changes made in Printer Information, Printer Preferences, Job Defaults, and Configure Communication (including "Printer's Network") options of the printer's window. Thus, if the zone is being changed, then you MUST close the printer's window after changing the zone, and open a new printer window by selecting the printer in its new zone before making any further changes to the printer.
This is the only option in the original Apple Printer Utility that behaves in this manner. This issue was fixed in the Apple Printer Utility 2.0 posted online.
This article can help you locate the software update mentioned here: