Custom paper height limit

[Ivan Mica]

Hello,

I would like to print onto very long continuous paper with my Cannon iP4700, however I crashed on some hard limit, that I can neither cross nor explain...

E.g.
 $ lp -o media=Custom.21x59.7cm out.ps
works perfectly, but
 $ lp -o media=Custom.21x69.7cm out.ps
does not even start to print (job gets however marked as completed)

I tried to experiment with the corresponding PPD, namely I increase the
 *MaxMediaHeight: "1917"
to
 *MaxMediaHeight: "2917"
and
 *ParamCustomPageSize Height: 2 points 257.96 1916.23
to
 *ParamCustomPageSize Height: 2 points 257.96 2916.23

with no visible effect... But this was really just an intuitive experiment - I have no previous experience with PPD, so maybe I was doing something wrong.

Can someone explain this behaviour or give me an advice, where to look to learn how to change the PPD appropriately?

Thanks in advance