PROBLEM of ORIENTATION : SOLVED. :-)
I had the problem, only by printing pdf files with pdf creator 1.7.2.
E.G. : a MS-Word file in landscape was correctly printed, but the additionnal page (landscape, coming from a scanned pdf file), was always in portrait...
Even when alone printed, a pdf scanned file in landscape was printed in portrait...
I solved it by unsinstalling last version 1.7.2 and reinstalling version 1.6.2.
Not beautiful, but efficient...