Our own wikis search in Advanced mode (German:Erweitert) by default (for signed-in and anonymous users):
http://species-id.net/openmedia/Special:Search http://offene-naturfuehrer.de/w/index.php?title=Spezial%3ASuche&search=x...
Compare http://en.wikipedia.org/w/index.php?title=Special%3ASearch&search=xzz which searches in default mode.
I cannot find (or remember?) the setting responsible for this. Looked through many pages, including http://www.mediawiki.org/wiki/Category:Search_variables
who can give me a pointer?
Gregor
mediawiki-l@lists.wikimedia.org