Add List Price To Products On Sale

Hello CS Gurus :)

When a product has a list price different to the selling price, both prices are shown.

When creating a discount through a promotion, the old price and the discounted price is shown.

How can I add the list price so as all three prices are shown in case of a promotion (i.e. list price, old price and selling price).

Thanks

Code modifications in templates are required to do it