I'm not sure really, as you say the set up on SUSE does seem to be different than Red Hat
This link might help:
It is about installing php5 but also has some useful info about php4 and the location of the correct httpd.conf (BTW note that it is httpd
.conf) on SUSE. I thought the section on "Making sure you have the correct Apache2 setup" might be of use to you.
Also to test php create a phpinfo file as follows
put it in the root directory of the webserver "/srv/www/htdocs/" and try to open it with your browser.
When you eventually see this file parsed you'll let out a big cheer