How to make MenuBar chnages Persistent par Document.

Hallo,
I can make disappear  some Buttons from a Menubar in a document). But 
After saving an reopening the doc, the buttons are "again" in place.

my code uses

oMenuBar.Persistent = true

In the ODK help i can find: If the property Persistent is *true* changes 
on the structure of the user interface element are written back to 
configuration source. When this property is changed, afterwards 
XUIElementSettings::updateSettings must be called so the user interface 
element tries to retrieve its settings from the new user interface 
configuration manager.  BUT wath mean this lines ?

There was a issue (46194) whois fixed ("false" wasn't working) , but now 
i think "true" is not working any more

Thank for any hint.

Fernand