CUPS drivers for wide printer

[m.roth at 5-cent.us]

I found the .ppd for our brand new HP z3200ps 44" printer - a coworker got
me the one from the Mac, and I edited it to separate out the Mac-only
commands (there's even an #ifdef in ppd language), and it prints; I don't
even need postprocessing, apparently... except that even though it knows
how wide the paper is (in this case, a 24" wide roll that came with the
printer), it refuses to print a picture that's horizontally wide
horizontally, it insists on doing it vertically. That is

          ========= saturn =========

according to print preview, wants to print

                ||
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              saturn
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Anyone here worked with a wide-format printer, and/or have a suggestion as
to what I need - is it something in the .ppd, or do I need a
post-processor, or...?

Thanks.

        mark