Problem drawing a pdf document (CGContextDrawPDFDocument)

Hi

I develop a QuarkXtension in CW 8.3. In this XTension there is a dialog
and 
I want to display a pdf document in a rectangle of this dialog. I use 
CGContextDrawPDFDocument to do this. But it doesn't work. The document
isn't 
displayed.
What could be wrong?
Has anybody a piece of sample code?

I tried the same using CGContextDrawPDFPage, but the class CGPDFPageRef 
isn't known. I included "CFPDFPage.h", but after that I have a lot of
error 
messages from the compiler. I don't know why. The class CGPDFDocumentRef
is 
known without including any header file. I know, somewhere it is declared,

but I am wondering why CGPDFDocumentRef is declared and CGPDFPageRef not.
Any idea?

Thanks.

Regards
Hans