Just a small note for people trying to use MediaWiki on Dreamhost. I first made a local installation which had this as $wgArticlePath:
$wgArticlePath = "$wgScript/$1";
For reason, that I haven’t yet found (and probably won’t find thanks to other more important stuff on my list ;-) ) this doesn’t work. It actually ends up in generating infinite URL redirections.
After switching to the more ugly but at least working …
$wgArticlePath = "$wgScript?title=$1";
The infinite redirections finally seem to have stopped :)