[CS3] Extending the Document Object Results an Error

Question

I'm trying to extend the Document object:
Document.prototype.myOwnMethod = function() {
/* some code here */
but I'm getting a Document is undefined error in Illustrator CS3
I tried extending the Application object:
Application.prototype.myOwnMethod = function() {
but I don't get any error.
How can I resolve this?
Thanks in advance....
-- Jeff

Answer 1

very old post, but not answered.
PathItem.prototype.nick ="pfad"
will work if a single Path is initialized before:
var p =activeDoc.selection.. or something
,otherwise not
to solve this i create my own obj.:
function Pfad(obj){
     this.nick = "bla";
     this.ai = obj; // to store the original Obj
var p = new Pfad(pathItem);
//then :
p.nick;
p.ai.fillColor;
my question is: is this the best solution or could it be done better?
thank you
Chris