Unofficial Symfony 1.5

Since the official support for Symfony 1.x has been interrupted in November 2012, a community driven fork of symfony 1.4 has being developed to support DIC, form enhancements, latest Swiftmailer, better performance, composer compatible and PHP 5.5+ support.

This unofficial version can be found at https://github.com/LExpress/symfony1.

And you can read the README file there to know what has been added.

Keep on mind as they mention in the README file “Do not use it for new projects: this version is great to improve existing symfony1 applications, but Symfony2 is the way to go today“.