Redmine

Could you point to the way this happens? I'm looking for a quick fix, my guess (so far) is that there's something broken in the permissions handling? How does the closed property manifest onto a plugin that is completely unaware of it?

I'll just update this for other people interested:
As stated in documentation for function permission in lib/redmine/plugin.rb:

:read => set it to true so that the permission is still granted on closed projects

So for permissions to be available for closed projects, you need to rewrite permission lines as follows:

    permission :view_dmsf_folders, {:dmsf => [:show], :dmsf_folders_copy => [:new, :copy_to, :move_to]}, :read => true