i applied a second patch for Ticket 13166.
i moved the discussion there. Maybe it's a bit overkill to post it here again.
https://bugzilla.wikimedia.org/show_bug.cgi?id=13166
I would call the Hook (i think one hook is absolutely appropriate) 'AlternativeTitleDBKey'
i defend all this on the bugtracker, so i am happy about your comments on what i wrote there.
Thanks in advance for all the input you gave me. i am happy for suggestions.
see you all josh