From the System Administration tool, you can access the Device Classes for the various Networks you have created.
From this Network Managed Device Classes window you can work with the Device Classes.
To Manage the Devices Classes list (and override Global Settings),
From the listing of Device Classes displayed in the Network Managed Device Classes window, select a Device Class, then click the Override Global Settings check box.
Next, select the Managed List button to view a listing of the Supported Device Classes shown in the Manage Supported Device Classes window.
Make your selections from the Supported Device Classes pane, and move them into the Managed Device Classes pane using the Add or Add All buttons. Note that you can also remove any unneeded classes using the Remove or Removal All buttons.
Click Ok when you have made all your additions to the Managed Device Classes pane. The Device Classes you added are now in the listing shown in the Network Managed Device Classes window.