Thread:Talk:MediaWiki/Install failed on CentOS 5.3/reply (13)

You could try updating, but I don't think that this would help you. This is no bug in MediaWiki, but a sub-optimal configuration on your machine. I don't think that this would have been "fixed" in newer versions of MediaWiki.

You could try recompiling PHP or to take another PHP package so that PCRE has full unicode support. Maybe your webhost also offers a newer PHP version, which has complete PCRE unicode support.