[R] Sweave with other fonts looks weird in pdf file

[Jeff D. Hamann]

I've become an avid user of Sweave and would like to able to use other fonts 
but when I added the following lines to a sweave file,

\renewcommand{\familydefault}{cmss}
\renewcommand{\rmdefault}{cmss}
\renewcommand{\sfdefault}{cmr}
\normalfont\normalsize

the pdf file generated with pdflatex the text for the sections that aren't 
generated by sweave (all the "non-chunks") have that "jaggedy" look when 
displayed in acrobat reader. When I print the document, the text looks fine. 
I'm using,

C:\st521\homework\hw1>pdflatex -version
MiKTeX-pdfTeX 2.3.1222 (1.10b) (MiKTeX 2.3)
Copyright (C) 1982 D. E. Knuth, (C) 1996-2002 Han The Thanh
TeX is a trademark of the American Mathematical Society.

and don't know if this is a sweave problem, MiKTeX problem, or something 
else.

Any ideas?

Thanks,
Jeff.


---
Jeff D. Hamann
Forest Informatics, Inc.
PO Box 1421
Corvallis, Oregon USA 97339-1421
541-754-1428
jeff.hamann at forestinformatics.com
www.forestinformatics.com