Contact support with the name on your server and it will be updated. I contacted them to ask when the update was planned on korben and they did the same day, just before answering.
What happened is that korben server had an hardware failture and it has been reinstalled on a new system with the old PHP. Maybe other servers had similar problem. Let them know and they'll fix really quickly.
Also don't forget that you can always compile your own version (both 4 and 5). In this way you can even enable extensions (eg. exif or sqlite for php4) and access (your) php.ini file.
In kbase you can find a simple guide to do so, I've created an improved version, easier, that soon or later I'll distribute.