I'v install ZenPhoto 1.2.2, and the SVN 3 day ago (3097), where it should be possible to do a manual image rotation.
The rotation radio buttons is present, in the album image view, but not active

'Rotation: none 90 degrees 180 degrees 270 degrees'

What am I missing?

For the information, do I also use ZenPage.

Within admin, Options > Image Display, verify that "Auto rotate images" is enabled.

Rotation (as the description says) requires a version of PHP that supports the rotation function. It the buttons are not active your PHP does not have the needed support.

Thanks, it was the image option settings which did the trick..