According to this page http://musicbrainz.org/label/c80d3a32-73d9-4c2a-b591-115edd0fa65b/annotation one should add a CC license relationship for Jamendo releases. This is not possible if Javascript is activated.

Example:
http://musicbrainz.org/edit/relationship/create_url?entity=f1f0fa1b-86d5-46d6-85b7-c2841196c2f6&type=release
1. Select "is available ... under CC license"
2. Enter the Jamendo URL like http://www.jamendo.com/album/98521
-> Problem: Selection changes from "CC license" to cover art
3. Change it back to CC license, enter license details
-> Submit -> Changed back to cover art again

Solution:

• Do not force all Jamendo URLs to be cover art
• Or at least: If a URL is recognized as Cover Art, but the user changes it to something else, stick to the user's choice

Workarround: Disable Javascript
(See the successull javascript-disabled edit here: http://musicbrainz.org/edit/15441395 )