Regd IGoCollapsible

Hi All,

I have a basic question. I am using GoDiagram 2.2.2 Version. I am not able to see the IGoCollapsible in Northwoods.Go NameSpace.
Could you please let me know in which name space can i get the reference? is this a Version problem or issue with my System only?

That interface was added in version 2.3.