routing 2 identical subnets

[Jacob Yocom-Piatt]

at work there are 2 pieces of heavy machinery that each are "hard-wired" 
to communicate on the, say, 192.168.101/24 subnet and i would like to 
access both subnets from a machine in the office on the 172.16.16/24 
subnet. to avoid the issue of having 2 routes to the same subnet, i plan 
on having an intermediate machine in front of each subnet that will run 
ipsec and then NAT the 172.16.16/24 host to a 192.168.101/24 address. 
this way i should be able to avoid the 2 route issue.

there are likely other solutions to this problem that don't involve 
ipsec and i am interested in hearing them. could the multiple routing 
tables feature be useful here?

cheers,
jake