(AS) User interaction level

Hello Everyone:

In a previous version of InDesign I had this Applescript statement in the script, and it worked just fine:

tell application "InDesign CS"

   set user interaction level to never interact

...

Now, working in InDesign CS5 the above statement does not work, even after updating the application label to "Adobe InDesign CS5." This script snippet does not work:

tell application "Adobe InDesign CS5"

   set user interaction level to never interact

...

I have tried several variations, including something looking like this:

tell application "Adobe InDesign CS5"

   set MyPreference to script preference

   tell MyPreference

    set user interaction level to never interact

   end tell

And this:

tell application "Adobe InDesign CS5"

    set user interaction level of script preference to never interact

It doesn't matter what I use, the script blows up (stops working) at that point.  So how does one set the user interaction level in Adobe InDesign CS5?

TIA,

John