Syncing issues between CE PDA & Boot Camp Mac


I have a Mac running Snow Leopard and have a boot camp partition where I
have Windows XP installed. However I am UNABLE to connect my old Windows CE Jornada 720 and sync. I have tried syncing via USB, and most recently purchased a USB to serial adaptor on ebay and connected it to Windows, installed the driver and still cannot sync. There is nothing wrong with the Jornada or its serial cable as the Jornada syncs just fine with my ANCIENT Windows 98 Laptop. What are your thoughts? Thanks..