Um, well question says it all - why is a question about fail2ban and ipfw off-topic for "serverfault" and gets migrated to "superuser"?
It's about server processes, right? Is it because it's MacOS?
Where do I begin? O right, at the fact that MacOS 10.5 is not supported by Apple basically since forever (August 2009, to be precise). Running this facing the internet is not at all a valid professional system administration approach.
I wouldn't have migrated this but closed outright with this close reason:
Questions should demonstrate reasonable business information technology management practices. Questions that relate to unsupported hardware or software platforms or unmaintained environments may not be suitable for Server Fault - see the help center.
Okay ignoring the tone set here, I try to explain what the problem is with your original question (which I haven't read because I did not find it in time).
Server Fault is a question and answer site for managing information technology systems in a business environment.
This is not about server processes (even a home DSL router has say a DHCP server) but questions regarding IT systems in a business environment.
One could say that your company issued MacBook Pro is a business environment but serverfault is a resource for people managing all the notebooks in a company, services on an business level (compare home-DSL router vs. company firewall system). But that's not the point.
On the other hand:
Super User is a question and answer site for computer enthusiasts and power users.
Often times there are similar questions on both sites, with the difference being the scale. I'll try to make an example to make this clearer:
Don't be disappointed if a questions gets migrated to another site in the stackexchange network. There are helpful and knowledgeable people on both (all) sites of the network. It's just that some questions can even be better answered by the respective other site.
It's the same as a programming question posted to serverfault would be better migrated to stackoverflow - because that's where the experts for that purpose are, and where people are expected to look for those kind of questions.
Stackexchange, isn't solely about answering your question for the moment, but to provide a resource for other people looking for this question in the future. People come to serverfault to find questions and answers about a business environment as they visit stackoverflow to find answer to programming questions.
Sure, given the right question someone on serverfault could answer my programming question but it wouldn't be found by people running in the same issue and looking for help and is therefore better migrated.
Your question was most likely migrated because it was not on topic for ServerFault.
Server Fault is for questions about managing information technology systems in a business environment and since Apple has stopped making server hardware (many moons ago) the position of OS X as a server operating system has also been very much in decline to the point where it is irrelevant for (almost all) professional sysadmins and you're much more likely to get answers on either SuperUser or Ask Different.