Reliable Penguin

If you have a server with PHP4 installed but need PHP5 on some websites then:

1. Install a custom build of PHP5 to /opt/php5.

2. Add lines like the following to your apache virtual host:

   AddHandler application/x-httpd-php5 .php 
   ScriptAlias /bin /opt/php51/cgi-bin
   Action application/x-httpd-php5 /bin/php5

You might also find the RemoveHandler directive handy to disable PHP4.