AvalonDock can't change InfoTip of DocumentContent after it was initialized?

Hi,

I have a class that inherits from DocumentContent class..

My class is called TabDocument, and I have an ObservableCollection<DocumentContent> called MyDocuments which is where all my documents tabs are in..

I am adding a new TabDocument to the ObservableCollection using:

string title= "Untitled";

MyDocuments.Add(new TabDocument(this, os, version) { Title = title, InfoTip = title });

So when my document is loaded it have a a Title and an InfoTip with values of "Untitled"..

But I want to change the Title & InfoTip after an event occured and after the TabDocument was initialized (when the user saved the document) so I do the following:

selectedDocument.Title = "NewTitle";

selectedDocument.InfoTip = "NewTitle";

Well - the problem is that the Title of my document changes.. but the InfoTip property does not..

I am using the newest AvalonDock built for .Net Framework 3.5 Client Profile

Thanks in advance,

Din.