hi,
apache2 is like a bleeding edge version and its gr8 for experimenting as
it includes loads of new features, apache 1.3x is a lot stable and is
used in production systems. now since development of php is hyper fast
when compared to apache, apache2 and php do not go together that well. i
use php 5 and apache2 but i use it only for learning purposes. most of
the webservers still run on php 4 and apache 1.3 combo as they are a
lot more dependable. so if i was running a mission critical system that
controls a nuclear reactor or something similar i would dare not go in
for an upgrade. Also to increase perfomance when it comes to php and
apache combo, compile php as a shared object and not as a cgi module. it
is a lot safer and faster. if ur main concern is to increase php
perfomance on apache there are third party tools like eaccelerator and
phpaccelerator that does all the dirty work for you
regards
Sudharshan S