docbook-xsl producing invalid FO? :(

I hope I explain this properly, forgive me if I don't.
I'm going out of my mind trying to figure this out - I've tried
everything.

This command:
  /usr/local/fop-0.20.5/fop.sh -d -xsl xsl/html/docbook.xsl -xml xsl/RELEASE-NOTES.xml -pdf index.pdf

Results in no idex.pdf being output.
Instead I'm met with lovely lovely errors like:

[ERROR] Unsupported element encountered: html (Namespace: default).  Source context: unavailable
[ERROR] Expected XSL-FO (root, page-sequence, etc.), SVG (svg, rect, etc.) or elements from another supported language.
[ERROR] java.lang.NullPointerException
org.apache.fop.apps.FOPException: java.lang.NullPointerException
        at org.apache.fop.apps.CommandLineStarter.run(CommandLineStarter.java:111)
        at org.apache.fop.apps.Fop.main(Fop.java:62)


I used xsl/RELEASE-NOTES.xml from the docbook distribution as an
example, on the assumption that it shold compile fine. the XSL output to
HTML fine, but I *really* need FO to work so I can output to PDF and
TXT.

I followed the install instructions for FOP from
http://www.sagehill.net/docbookxsl/InstallingAnFO.html

-- 
Avleen Vig
Systems Administrator
Personal: www.silverwraith.com
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