I've tryed to compile php for apache 2.0.16, heres the 
error I got : 
sapi_apache2.c: In function `php_input_filter':
sapi_apache2.c:248: too many arguments to function 
`ap_get_brigade'
sapi_apache2.c: In function `php_output_filter':
sapi_apache2.c:337: too many arguments to function 
`ap_save_brigade'
sapi_apache2.c: In function `php_register_hook':
sapi_apache2.c:443: warning: passing arg 2 of 
`ap_register_input_filter' from incompatible pointer type

I took a look at this file and at util_filter.h from 
apache's include dir and found out that only three args 
are necessary to ap_get_brigade. I've looked a bit more at 
the code and tryed this modification on sapi_apache2.c :

if ((rv = ap_get_brigade(f->next, bb, mode)) != 
APR_SUCCESS) {

aparently it now works (I managed to display php pages 
after that...)

It's now up to the php developpers hands and brains to see 
if my modification is interresting or not.