From a posting on PHP Magazine's website:

OETrends.Com has a report on how, with version 5, Zend is gearing PHP as one of the flexible aids available for building and updating web-to-enterprise software, and making it more appealing to enterprise IT managers and developers.

They report that PHP 5's improvements arise in strategic areas, namely, native SOAP support, stronger dynamic SQL support, better XML integration, and native OO support that allows better sync with Java and .NET.

Zend's PHP 5 InfoCenter includes a full list of PHP 5's enterprise features. Read the detailed report here.

They also mention a few other resources for anyone interested in further reading on the topics mentioned...