Thus instead of the ":" being a reserved
character anywhere in a
title, only "user:", "talk:", "wikipedia:" etc. need to be
reserved. Any other uses of colons should be fine. This will let us
have entries for books with standard formatting of the subtitle (e.g.,
"The Muggles: A Tale of Woe") or other natural uses of the colon.
There is a simpeler solution. The actual contents of Wikipedia get the
namespace "content:". If everything is prefixed with a namespace then the
first colon is always the end of the namespace.
That's perfect.