Turn PDF into grayscale

[Pupeno]

Hello,
I have some color PDFs I'd like to turn into grayscale, any ideas how ?
I have tried printing to PDF (the pdf itself) and setting it to grayscale, but 
the PDF ends up in color anyway.
Thank you.
-- 
Pupeno <pupeno at pupeno.com> (http://pupeno.com)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 191 bytes
Desc: not available
URL: <https://lists.ubuntu.com/archives/kubuntu-users/attachments/20060626/2fc19f2f/attachment.sig>