DOCBOOK: DocBook print version DSL problems

I don't know what to do to solve this but using the DSL version of the
docbook that came with Norman Walsh's book I get this error message:

jade:/home/ldp/SGML/style/dsssl/docbook/print/docbook.dsl:1:73:W: cannot generate system identifier for public text "-//James Clark//DTD DSSSL Style Sheet//EN"

It's true. I couldn't find this declaration on any of the "catalog"
files that came with the book. Where can I get a file with this
declaration? Or, is there a better way for generating a printable
version of a DocBook document? The command I used for this message was

[godoy@nexus principal]$ jade -t sgml -d /home/ldp/SGML/style/dsssl/docbook/print/docbook.dsl servidor.sgml

but I've also tried with other output formats (rtf, tex, etc.) always
getting the same error messages.

With the "html" version of the DSL I get similar error messages.

Thanks for any clues or help.
--
Godoy.	<>               GPG Fingerprint
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