How can I change line (Shape Control) height Dynamically in reports

Eg: In PO Report, transaction level i added vertical line, and my item description height is dynamic so i want to make the line height also dynamic, I tryed to set the auto property but it is not working


set width to 80characters and dynamic property to yes.then the height of the field will be changed dynamically.

Thanks & Regards,

Britto John Baskar.A