reverse dns for multiple domains on same subnet

[Nick Trenary]

I have two domains on my subnet, call them domain1.com and domain2.com on 
192.168.10.0.  How is reverse DNS configured?  There can be only one 
10.168.192.in-addr.arpa zone file, right?  If so, how is it configured for 
multiple domains if both domains point to the same IP address?

Thanks,
Nick Trenary