tagCustom + Raumfeld

[workspace]

I have a similar setup (Raumfeld and Minimserver on a Synology NAS) and still have problems for albums with multiple artists.
When I'm using AlbumArtist.displayRole={artist} it kind of solves one part of the problem. But since Raumfeld only reads the first instance of a upnp XML tag (same problem with genres) I lose all the the Artist Information. (every track of that album would have "Various" as artist)

I realized that Raumfeld works correct together with twonkyserver.
twonky uses a XML tag named upnp:albumArtist and obviously Raumfeld is parsing this to handle albums with multiple artists.

so my question:
Would it be possible to introduce something like AlbumArtist.displayRole={albumArtist} so that I get a XML tag like upnp:albumArtist?

Thanks for the help

Michael