When tiling over existing tile how can I raise the drain?

When tiling over existing tile how can i raise the drain?
There is a product called the Extendo Drain System. It is a set of plastic rings (that come in different diameters depending on the size of your drain) and you mount them under your existing drain cover. They also provide you with longer mounting screws. Try some of your local tile stores or try [www.tiletools.com]
Another way would be to purchase shower strainers in the correct drain size plus longer screws and build the drain up that way. Good luck, Tom