Does anyone know if it possible to make the Navman 4460 work with the Treo 600?

I realise that the bundled GPS receiver is a bluetooth model, so this will not work, but their software looks very good. Would it be possible to use a wired GPS receiver with the software on the T600?

I searched this site, google and navman's site, and not found an answer. This lack of info makes me suspect that it's not possible, but maybe someone knows for sure?