Forms.ToolTip Control is not behaving properly.

From MSDN

"AutoPopDelayproperty enables you to shorten or lengthen the time that the tooltip window is displayed when the mouse pointer is over a control."

But setting AutoPopDelay more than 5000 is not working at all.ToolTip is not hiding even after long time.

Will somebody suggest what to do if I want to see tooltip for time larger than 5000.