a) You can move a standard wiki page to a new name having a relational name space prefix. That should be avoided and yield an error message.

b) When that is fixed, Omegawiki pages of said type need to be moved back to name space zero with names allowing them to be edited normally, moved, or deleted. A mainainance script should do that and be run automatically during the upgrade process.

c) See also: http://www.omegawiki.org/index.php?title=Meta:Insect_room/Archive/2013&action=submit#Expression_linking_to_Wiki_page:

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URL: http://www.omegawiki.org/index.php?title=Meta:Insect_room/Archive/2013t#Expression_linking_to_Wiki_page: