For instance, in xml-streaming.xml (qtxml module), qdoc 6.3.0 generates the following output:
<db:extendedlink><db:link xlink:to="xml-namespaces.xml" xlink:title="prev" xlink:label="An Introduction to Namespaces"/></db:extendedlink>
This DocBook excerpt is invalid. With DocBook 5.2 CR 1 schema, Jing produces the following errors:
The correct DocBook output for that link would be:
<db:extendedlink xlink:type="extended"><db:link xlink:to="xml-namespaces.xml" xlink:title="An Introduction to Namespaces" xlink:type="arc" xlink:arcrole="prev"/></db:extendedlink>
Here is a patch that should fix the issue: https://github.com/dourouc05/qttools/commit/c31bf7b63f19770a2ed1d0c45de3e30ff69d27b7 (I could submit it to code review, but I have to reinstall everything first). Compared to this patch, new lines should be added when the <db:extendedlink> elements are closed.