Acrobat Reader X & app.newDoc()

Hello,
 
I've created a form with some buttons on it on
I've a trusted function in the Javascripts folder of my Acrobat Reader X :
 
createBlank = app.trustedFunction(function(doc, path, lines) {
app.beginPriv();
doc = app.newDoc();
doc.saveAs("blank.pdf");
doc.closeDoc(true);
app.endPriv();
}
 
But in the console appears the message:
NotAllowedError: Security settings prevent access to this property or method.
App.newDoc:3:Field Submit:Mouse Up
 
I tried to create a new document and extend Adobe Reader rights but no luck.
 
What can I do?
Thanks for your help.
 
Best Regards.