Rose,
The only fully qualified reference to that file should exist in the struts-config.xml file, so moving that file should be fine as long as you update your struts-config.xml file after (down in the <message-resource> section).
However if you have manually loaded that file in your code anywhere, then you must update those references as well. I would first search your entire project for “ApplicationResources.properties” and see what you come up with and change the references you find to it.