Maya's project curve only works on Nurbs surfaces. So you could project the curve onto a Nurbs surface and then convert to polygons, but that is kind of an annoying workflow. Your other option is to make your mesh "live," and then any curve you draw will be snapped to the polygon surface.
Yeah shapemerge are pretty sweet under Max, hhmm but this made me realized that you have to actually project a Nurbs curve on a Nurbs surface in Maya for this to work. With a ll the plugins coming for Maya is there not a way to achieve this in Maya using polygons only ?