albumartist is shown as artist

I checked the database. The "albumartist" tag is stored in the "ARTIST" column of the "DETAILS" table.
The "artist" tag itself is used in the "CREATOR" column of the "DETAILS" table.

Interesting. But "CREATOR" is not offered to my client.

But I have to say that I don't understand the UPnP protocal exactly. So I don't know who (client or server) is repsonsible for what I see on the client menu.

Database names do not have to correspond to the tag names. The client requests and the server responds with the requested info. Although, some clients will do additional processing that can change results. Look online for a pdf file "UPnP-av-ContentDirectory". Get the latest version and read up.

I think I didn't understand you or I wasn't good in formulating my report.

An mp3-file has two tags %albumartist% and %artist%. But my clients only see %albumartist% which is names as "Interpret". But htat is wrong.
The "Interpret" is %artist%. The "Album Interpret" ist %albumartist%.
Both should be offered. But I thinky they are not.

This worked fine when using e.g. Twonky.

If you are talking about upnp:albumArtist, I don't think it's part of upnp specifications. Check out the "UPnP-av-ContentDirectory" pdf.

I believe what the OP is requesting is that the scanner save and later use the role attribute for compilations:

<upnp:artist role="AlbumArtist">Various Artists</upnp:artist>
<upnp:artist>The Track Artist</upnp:artist>

See Appendix B.3.1.1 in http://upnp.org/specs/av/UPnP-av-ContentDirectory-v2-Service.pdf
See also http://wiki.openhome.org/wiki/Av::OhMetadata

The attached patch solves this problem quick and dirty. Simply store creator in metadata and not artist.