This should be the final beta release of MediaWiki 1.3.0; the final final version will be released in a few days after some more bug fixing and polishing up of documentation and installation.
Beta 6 includes a security fix: earlier 1.3.0 beta releases may be vulnerable to a PHP inclusion attack if you have allow_url_fopen and register_globals on (this is the default configuration in PHP 4.1.x, but register_globals is off by default in 4.2.x and later).
Note that while MediaWiki through 1.1 required register_globals to be on, 1.2 and 1.3 *do not*. If you have register_globals on, you should turn it off unless you are absolutely sure you require it for some other package. See http://php.net/register_globals for general information.
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