The goal for PHP6 is basically to provide good unicode support (strings internally as unicode etc.) However due to problems and internal conflicts the effort w

The goal for PHP6 is basically to provide good unicode support (strings internally as unicode etc.) However due to problems and internal conflicts the effort was stopped a few years ago and there has been no progress since. If this goal hadn't been stated PHP 5.3+5.4 would probably have been PHP 6 (they have some major new features). Core API cleanup never has been (and it doesn't look like it will soon be) a goal for a future release, unfortunately.