serial attached printer problem

[Andreas Sumper]

Hi list!

I want to use cups 1.2.1 with a thermo-printer which is attached through
serial port /dev/ttyS0 on a linux system.
I installed cups and added a printer. The manufacturer of that printer
told me, to use the drivers of a HP DeskJet 350c which should be part of
CUPS iirc. If I try to write ASCII-files on the printer using minicom,
everything works fine. But if I try to use this printer with cups, all I
get is
ERROR:
	client-error-not-possible
I set the permissions on /dev/ttyS0 to 777 so that it is writeable by
the whole world. And I configured the device in cups the same as I did
with minicom, but it is allways the same error-message.

Does anybody know about such problems and if yes, can anybody help?

Thanks in advance!
Andy