[xml] xmllint: validation of XML files with XInclude-d documents maybe broken

[Daniel Leidert <daniel leidert spam gmx net>]

Hello,

See the file http://debian.wgdd.de/temp/howto-mimedef.xml as example.
This file is a DocBook article, that xincludes several other XML files
for appendices or other parts of the article. Now I want to validate the
file. Therefor I ran:

xmllint --xinclude --noout --valid howto-mimedef.xml

and I get a lot of errors. It seems, that e.g. the XIncludes are not
included. xmllint complains about the xi:include elements itself. And
then it also seems to try to separately validate the xincluded files
too, which of course fails for e.g. the included gfdl.xml file, because
it does not contain a DTD. But if I do:

xmllint --xinclude howto-mimedef.xml > test.xml
xmllint --valid --noout --valid test.xml

everything is fine (the resulting XML file is valid). So I would expect,
that a

xmllint --xinclude --noout --valid howto-mimedef.xml

Am I doing something should also work and not fail. Am I doing something
wrong? Does xmllint work as expected here?

Regards, Daniel