Images are broken on multisite drupal - wrong modulpath

Drupal 6.10
BG 6.x -3.0
Multi Site installation.

I don't see any Image I only receive broken images.
The reason is a missing slash between the root an the multisite part.

On the node with a gallery images are there like this:
src="http://mysite.de/index.phpsites/mysite.de/modules/brilliant_gallery/imag..."

The Slash is missing between index.php and sites
I also think that the index.php is wrong there.

If I try this URL it works:
http://mysite.de/sites/mysite.de/modules/brilliant_gallery/image.php?img..."

Second problem is that is can't switch the images from visible to invisible on manage Galleries.
I can see all folders there but there are no images - some problem than described above.

If I tick the checkbox "visible" turns to "saving..." and that's it.

Help wanted ;-)