https://sourceforge.net/tracker/?func=detail&aid=3028248&group_id=152762&atid=785194

Currently, ZK allows only one resource file (/WEB/i3-label.properties; customizable by http://docs.zkoss.org/wiki/Developer_reference_Appendix_B._WEB-INF/zk.xml_Library_Properties#org.zkoss.util.label.web.location).

It is better and clearer to allow users to specify one or multiple resources in zk.xml.

<label-resource>
<path>/WEB-INF/foo/users.properties</path>
<charset>UTF-8</charset>
</label-resource>

In additions, it is better to allow the developer to specify resource files in a ZUML page, such that the resource file used and loaded only for a particular page.
<?label-resource path="/WEB-INF/foo/users.properties" charset="UTF-8"?>