
"PHP 4, deployed on tens of millions of servers globally, is among the most successful languages of all time. But its run is coming to an end. Active development for the scripting language has been discontinued and security updates will conclude in August. And for some developers, PHP 4 will be history before Valentine's Day. On February 5, a group of influential Open Source projects will collectively stop all new development on their respectively platforms using PHP 4. However, there are still some holdouts opposing a complete transition to PHP 5 and it's
not entirely clear whether or not PHP 4 will ever truly disappear."
Member since:
2005-07-06
Uhmm, no. You can have one as mod and the other as cgi. But not both mod (the way almost everyone runs php) at the same time. Thus, conversion is not as easy as it should be. (Or maybe not even possible.) Might there be some function available in one version that doesn't exist in the other, and then there are the associated performance issues.
Just think what would happen if Oracle or MS said "You can only have one DB engine active at a time.", I can tell you what would happen, no upgrades.