I'm happy you got apache2 working.
My guess is that you have two installations of apache2 on your server.
One is in /etc/apache2/ which is where I think SUSE puts it. I'm thinking that you must have inadvertently selected the apache2 SUSE package when you were installing other packages. Assuming this was running, it also explains your problem above. The trouble with this is that with SUSE's version, I could never successfully install
libapreq2 and I couldn't find anyone on the web who had succeeded with this either.which is where its put when installed from source. This is the installation you have to use. When you write "/usr/apache2/bin/apachectl graceful" I assume you really mean "/usr/local/apache2/bin/apachectl graceful" and this must be executed after a server reboot. The reason is that SUSE sets things up its own way and I don't know how to use their system services to start /usr/local/apache2. What you probably see in system services is /etc/apache2 which you don't want to use. At a minimum, you should disable this service so it doesn't start at bootup. I assume you can delete /etc/apache2 but that will probably leave vestiges around. My guess is that you can use the SUSE package system to remove /etc/apache2 completely and I don't think that should interfere with /usr/local/apache2 but I don't know for sure and I certainly haven't tested this.
Your second installation is in /usr/local/apache2/
I probably should ask a unix guru (or do some research) how to automatically start /usr/local/acache2 at startup. If I find out, I'll add it to the instructions.