Major Description
Currently org.apache.wicket.Page.isBookmarkable() checks whether the page is bookmarkable by checking whether it have either default constructor or a constructor with one parameter of type PageParameters.class.
I think this logic should be delegated to the configured org.apache.wicket.IPageFactory because org.apache.wicket.session.DefaultPageFactory works with these two constructors but custom IPageFactory can work with more/less/other constructors.