Konica Minolta Bizhub c252 force Grayscale

[Dan]

Hello,
please can you help me with setup konica minolta bizhub c252
I want to set it to print only in grayscale, not in color.
I use PPD file from HP LaserJet 9000 Foomatic + Poscript EN
It works fine but on the printer counter printed pages are between full
color however they are black :-/
When I use some  HP LaserJet 9000 Foomatic + pxlmono EN
counter problem is right but printer put clear pages between
printed documents. If it is possible to solve this problem by the removing
clear pages it is no problem, but I have no idea how to solve it.
thanks & regards
Dan