this sounds painful.
i would just determine the vendor of your hardware, visit the website and
download the drivers and burn em to cd.. then just 'neakernet them to the windows box.
anyway.. if youre feeling crazy.. I believe you can get serial to ethernet hardware..
that sounds a bit PBX ish though (traditionally for multiplexed ip phone systems as i recall) although cromp usa has serial style (com3) to network devices that enable a serial
printer to be used over the network.. i believe they can be configured the way you want.. ..crude though
then use mini conf to do the dirty work from the linux side via modem or comm..
or you could use hyperterm in windows to accomplish the same.. you may require a comm1 db 9 male to rj45 ethernet connector to pull it off either way..
I just dont know if you can dial out over com1/3 though...
hope this helps.