Change path to resourcebundles and theme.properties-file

Is there a way to change the path to the resourcebundles?
When I write

${msg(“message”)}

in the ftl-files that piece of code is replaced by the value that is linked to the key ‘message’ in the resourcebundles. The resourcebundles can be found in the messages-folder;
messages/messages_en.properties
messages/messages_fr.properties

What I want to change is that when I write

${msg(“message”)}

I want to find a message in;
messages/subfolder/messages_en.properties

How can I achieve this?

Same for the theme.properties-file.