[Quark & Leopard] Make page at end won’t work

When testing some Quark-scripts on Leopard it seems this code is not working anymore. It used to add new pages of a certain master spread.

tell application "QuarkXPress Passport" 
   tell document 1 
      make page at end with properties {master spread:"Name of master page"} 
   end tell 
end tell

Anybody who knows what’s changed or why it isn’t working or can test this lines in Quark 7.3.1 on OS 10.5.1?

Thanks.
Kjeld