FM Server Advanced Setting up IWP to restrict IP addresses

[mycaMKD]

So we've been using a custom IWP database for a while using Filemaker Pro Advanced, and setting it up to allow only certain IP adresses to access it is as easy as pie.

But our needs now require Filemaker Server Advanced, as we need to allow more users to access the datatbase, but I can't find any info on allowing only certain IPs and blocking other IPs to access the file.

I've installed FIlemaker Server Advanced 12 on a new Lion Mac mini Server, and would greatly apreciate any input of how to only allow specific IPs to access IWP, ideally what is the best way around this, should I use the Firewall or edit the Apache files. Whichever way is best any clear instructions on how to acheive this would be greatly appreciated.