Multiple wicket.properties files in uber JAR

I'm attempting to create an uber JAR using the Maven shade plugin and
running into an issue shading wicket, wicket-extensions and
wicket-devutils. All 3 of these module contain a wicket.properties file
that point at their respective Initializers. The problem is that when I
create the shaded JAR, the wicket.properties files all want to live in the
same place and overwrite each other. I can combine them into a single
wicket.properties file, but when the properties are loaded
via addInitializer(properties.getProperty("initializer")); only the last
one in the file is used.

Has anyone ever created an uber JAR with wicket and wicket-extensions (I
can drop wicket-devutils if needed)? If so, how did you do it?

If I needed to hack this together, knowing the names of the Initializers,
can I call them "manually"?

Thanks...

Bill-