Bug 67513 [R21PRES] view tab tool tip inconsistent with 2.1
In 2.1, the tab item tool tip appeared in the stack's title bar, not on the tab item itself. The r21presentation currently puts the tip on the tab item. I'll attach a patch that fixes the problem.
bundles/org.eclipse.ui.presentations.r21/src/org/eclipse/ui/internal/presentations/R21BasicStackPresentation.java
list.add(part.getControl());
			if (getPaneFolder() != null)
				list.add(getPaneFolder().getControl());
		} else {
			if (getPaneFolder() != null)
				list.add(getPaneFolder().getControl());
			if (part.getToolBar() != null)
				list.add(part.getToolBar());
			if (part.getControl() != null)
				list.add(part.getControl());
		}
		return (Control[]) list.toArray(new Control[list.size()]);
	}
	protected void showList(Shell parentShell, int x, int y) {