DOCBOOK: RE: DOCBOOK-APPS: Getting Rid of Character Entities inDocBook XML Docs

This test file works fine for me:

<!DOCTYPE para SYSTEM "/share/doctypes/docbook/xml/docbookx.dtd">
<para>This is a&nbsp;test.</para>

I've tried exactly this test file with my xalan xsl processor and got the
result:

Parse of file:/home/andi/docbook/html/docbook.xsl took 74306 milliseconds
========= Parsing /home/andi/docbook/test/test.xml ==========
file:/home/andi/docbook/dbpoolx.mod; Line 4089; Column 3
XSL Error: Could not parse /home/andi/docbook/test/test.xml document!
XSLT: The markup declarations contained or pointed to by the document type
decla
ration must be well-formed.
Xalan: was not successful.
XSLProcessor: done

	I would like to ask people, why does the parser fail exactly at this
line(line 4089) every time I want to parse a Docbook document. I'm using
Linux platform, and DocBook DTD V4.0beta6. It must be some stupid
configuration problem or something else, if others succeeded.
	I know, it has no direct connection with the subject, but I think there
could be related to parsing entities in general.
	Can somebody tell me more about his own experiences?

	Thanks for your time,
	Andrea