The Java Documentation should state that a JNLP file is an XML file and is case sensitive. For example, in addition to the actual JNLP spec, this page should likely be updated:

https://docs.oracle.com/javase/tutorial/deployment/deploymentInDepth/jnlpFileSyntax.html

For example:

This topic describes the syntax of the Java Network Launch Protocol (JNLP) file for rich Internet applications (RIAs). It should be noted that because the JNLP file is XML, all elements and their attributes must be entered in lower case.

Also, this related page (below) probably needs to be updated. At minimum, the reference to the sun.com mailing address should be updated. If there is a complete spec somewhere, a reference to it should be added to this page.

http://www.oracle.com/technetwork/java/javase/jnlp-spec-log-139509.html