Gentlemen, how may I prevent users from creating pages whose titles match a certain regular expression?
Sure there is Special:ProtectedTitles, but that isn't for regular expressions (and how one puts things into it isn't clear.)
Yes, there is $wgLegalTitleChars, but that isn't a regular expression either.
Yes there are $wgSpamRegex and $wgSummarySpamRegex, but these are for the page bodies, not the titles.
Hmmm, need an array of arrays($namespace,$regexp,$message_to_print_when_they_match_that_regexp). If $namespace is NULL, match any namespace.