Substitute for lactose in sweet stout?

I would like to make a Sweet Stout but unfortunately am one of those guys that are lactose intolerant. Are there any substitutes for lactose?

cheers

I just brewed a sweet stout and used Gambrinus Honey Malt instead of lactose.
Not sure if that still qualifies as a sweet stout, but its sweet and it turned out pretty tasty

Malto Dexterine.