Bug 388668 recently fixed upstream
FYI, this bug was eventually found out to be caused by wrong gdkevents
delivery order by the gdk/dfb library and was recently fixed upstream .
Anyway, ATM we don't necessarily need a backport of the patch since is
was already fixed with a workaround  in the cdebconf GTK frontend.
If/When we'll switch to gtk/dfb 2.10, we can close this bug and remove
workaround code from gtk frontend.
(mail sent to BR but previously not cc'ed to d-boot too)