You are confusing wireframe and hidden lines. I've just proven that hidden lines can be shown as dashed on a hidden line [not wireframe] internal engine 3D view by enabling this function on the Special Menu. It ends up looking as i expect that you would want.
Enabling the Special Menu is tricky. I can't remember how offhand, and it depends on your operating system. Search the forum for "Special Menu Enable" instructions.
Dwight Atkinson