I just upgraded a client that wanted php 5.3x and ran into a small issue with apache2 php5.conf
File is /etc/apache2/mods-enabled/php5.conf
In PHP 5.2 and below versions that config file has..
Which was just fine because the apache2 php mod allowed that directive however 5.3 and above this is depreciated now and that directive must be changed to
This conf change is for both lenny and squeeze. Users that use the dotdeb repo's need to make a note of this.