Your question would be better placed in a different forum (this one is for questions about javaranch, not about java). Hang on while we move your post to a forum where you're more likely to get the help you're looking for.
A tip for the future: you might want to use the special "code" tags around your code so that we can see the code itself instead of seeing how it is rendered.
The only way to do this would be to write your own classes to extend Struts. The "out of the box" installation reads the resource properties files once at startup time and does not refresh them until the application is restarted. Note that it is not necessary to restart the server. It is necessary to restart the web application.