Latest Magento 0.6.12510 gives when trying to install
Fatal error: Call to undefined function simplexml_load_string() in /var/www/magento/htdocs/lib/Varien/Simplexml/Config.php on line 266
I am running php-5.2.4 on a Gentoo-box. Extensive Googling shows that I am the only one on earth to have this problem.
For Gentoo-users: add “xmlsimple pdo mysqli” to your dev-lang/php entry in /etc/portage/package.use file. My whole entry reads like this (which is probably more than one actually needs for Magento)