AppleScript and Xcode error -10008

I am working on a tool similar to the one described in this question, to build and run an Xcode project via AppleScript, in order to automate testing. I am getting the following error message:

Xcode got an error: The specified object is a property, not an element. (-10008)

from the line

set active buil开发者_Go百科d configuration type to build configuration type "Debug".

Has something changed in AppleScript and/or Xcode that would break this line? If yes, is there a new way to accomplish the same thing, or at least something similar?

I am using Xcode 4.0.2 on a Mac running OS X 10.6.8.

That's the problem. You see, Apple rebuild Xcode and it's workings, and some AppleScript code (including this one) does not work anymore.

I don't think that there is a solution, unless Apple releases something. I guess they just expect you not to use AppleScript.