The Joomla Project announces the immediate availability of Joomla 1.6.4. This is a security release. This release corrects four security issues and fixes an issue relating to version upgrades.
Note that version 1.7.0 is scheduled to be released on 19 July 2011. Users planning to upgrade from version 1.6 to 1.7 will need to be running version 1.6.4 in order to upgrade to version 1.7.0.

Important Note: A security fix was made for the Category List layouts for articles, contacts, newsfeeds, and weblinks as well as the Featured Contact list. If you have created a template override for one of these layouts based on the core layout, your file could contain this security issue. Please see the release FAQ for more information.
The Production Leadership Team's goal is to continue to provide regular, frequent updates to the Joomla community. Learn more about Joomla! development at the Developer Site.

We are familiar with the implementation of the upgrade and are currently upgrading multiple sites CONTACT US fora free proposal to update your site.

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