Different DNS replies depending on IP block

[Kurt Kraut]

Hi,

I own a service that has mirrors all around the world. I'd like to
MaraDNS to respond a DNS request of my A ADDRESSes differently,
depending on the IP block that made the request

For instance, from a computer from an ISP provider would have this:

[root at computer1 etc]# host www.maradns.org
www.maradns.org has address 209.172.32.214

And another person from another ISP would have:

[root at computer2 etc]# host www.maradns.org
www.maradns.org has address 74.125.45.83

Anyone has a clue how I could do that ? Thanks in advance