In /docs/dtd/jboss-web_4_2.dtd the suggestd DTD url is "http://www.jboss.org/j2ee/dtd/jboss-web_4_2.dtd", but at this location I do not find the 4.2 files.

Line 15 of jboss-web_4_2.dtd seems to be invalid:
<!ENTITY % service-ref SYSTEM "./docs/dtd/service-ref_4_2.dtd">
The relative path causes problems, e.g. Eclipse cannot evaluate the DTD and so it cannot validate a jboss-web.xml file or provide content assist. Shouldn't the URL point to http://www.jboss.org/j2ee/dtd/ either ?

Same problem for jboss-client_4_2.dtd, jboss-app_4_2.dtd and jboss_4_2.dtd.