using params:
xfreerdp --plugin rdpdr --data serial:COM1:/dev/ttyS0 -- IP
shell print:
registered device: COM1 (type=1 id=1)
the serial printer is: GPrinter GP5860III (http://www.gainscha.com/products_show.asp?lan=zh-en&skin=2&newsid=141577051)
print test page on windows xp, the GP5860III printer print a little and then stop.
on windows xp,it report can not print.
I also tested rdesktop .the serial printer on the rdesktop work well.