I think this issue might me related to some themes only.
Could you test this one? That's the theme I found the issue.
http://gnome-look.org/content/show.php/Doe+GDM?content=52791
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Bug when first changing theme
https://bugs.launchpad.net/bugs/172927
You received this bug notification because
I've just a made a fresh Gutsy install on another PC, changed the theme
to Human List and the problem happened. It seems that it changes to
random mode and the themes Circles and Happy GNOME ar the defualt for
this option.
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Bug when first changing theme
https://bugs.launchpad.net/bugs/172927
I think it happens when the configuration file is first changed, or
created, don't know how it's stored . The steps are the same above.
--
Bug when first changing theme
https://bugs.launchpad.net/bugs/172927
You received this bug notification because you are a member of Ubuntu
Desktop Bugs,
Taking another look to the image, besides the two themes mentioned
above, I noticed that the random theme mode was also automatically
selected.
--
Bug when first changing theme
https://bugs.launchpad.net/bugs/172927
You received this bug notification because you are a member of Ubuntu
Desktop