Problem generating a PDF file from a postscript

Hi,

Using Pagemaker, I did create a *.ps file (postcript file).
Then I dropped it in Adobe Distiller (version 7) in order
to generate a PDF file from it: The Postcript file is actually about 15 pages. Once dropped in Adobe Distiller, the first three pages are
generated correctly...but at the 4th page, I continuously get the following error:
"Error undefined, Offending Command: sBdx ] %%
Stack:0.0
[]
10.0
0
0
1.0
(o)
-mark-
%% [Flushing: rest of job (to end-of-file) will be ignored]%%
%%[Warning: PostScript error. No PDF file produced.] %%

"

Just in case it helps:
-OS is windows 2000 Pro
-Acrobat Writer 5 (Also present in the PRINTERS directory)
-Acrobat Distiller 7 (Also present in the PRINTERS directory)