Midgard is going PHP5-only

The next planned release cycle of Midgard CMS, version 1.9 will drop support for version 4 of the PHP programming language. The reasons for this are that PHP5 provides better performance and that PHP4 has received an end of life status.

More information from a blog post by Henri Bergius:

This makes us free to focus on the PHP version (and other dependencies) that work best with our framework. Midgard core developer Piotras has estimated that some Midgard functionalities like Query Builder will be substantially faster on PHP5.

An important point also is that the PHP part of Midgard is MidCOM, a quite large object-oriented component framework. While MidCOM has been possible to develop on PHP4, new OOP features in PHP5 will make the code much easier to develop and understand.