[Mediawiki-l] Protected titles howto?

[Daniel Barrett]

How do you enable MediaWiki's "native protection of nonexistent pages"
mentioned at:

http://www.mediawiki.org/wiki/Project:Protected_titles#Method_1:_Protecting_a_nonexisting_page_.28preferred.29

I've searched meta and mediawiki.org but can't seem to find the
instructions.

I thought it might involve the page MediaWiki:Titleblacklist, but when I
add entries, they don't seem to have an effect (1.13 alpha).  Also
http://meta.wikimedia.org/wiki/Help:Special_page#Protected seems to imply
this system message is just an alternate method.

Thanks!
DanB