Creating Duotones?

System

Hi all.

Has anyone tried to create Duotones with a task? If so, how have you done it?

Photoshop 7.0 has a "Duotone" image mode, but the MediaBin Color Converter primitive does not have it.
Also, in Photoshop you can save a Duotone Options file (.ADO), but I haven't been able to find if and how I can use it in a MediaBin primitive...

Thanks in advance...

Folco