Interpreted modules with additional m-files

Hello!
I wrote a pack with custom AWE modules and converted them to be interpreted modules. Besides the usual prebuild/set/etc matlab files, I have additional custom m-files (for example like a class that is instantiated within a module's m-file) that are located in the same "matlab" subfolder just like the typical custom module m-files. However, I cannot open my modules in AWE-standard as the Matlab runtime says that it cannot find my additional m-files. Is there a certain default folder in the AWE-standard directory tree for such custom m-files? Or is it in general not possible to use custom m-files besides the default m-files used for a custom module?
My current work-around is to copy all the additional m-files into my modules' m-files - but this is really ugly..

Thanks a lot!