Cisco router to check source address for routing

I have 2811 and 2621 routers that I am working with.  I would like to be able to route a particular workstation to a different gateway of last resort to test out a new firewall.  All other systems should go the current firewall which is the existing gateway of last resort.

Here's what the router table should look like (if possible):

Source          Mask                            Destination             Mask                   Next Hop
---------          ---------                        --------------            ---------               ---------------
10.1.1.100     255.255.255.255         0.0.0.0                    0.0.0.0                10.1.1.2
0.0.0.0           0.0.0.0                         0.0.0.0                    0.0.0.0                10.1.1.1.

As you can see, I want 10.1.1.100 to use 10.1.1.2 (new firewall) while all others should continue to use the existing firewall at 10.1.1.1    

I know that the XP workstation can have its local route table modified, but I would prefer to handle this at the router as it is going to expand to many workstations as I migrate them over to the new firewall.

Any suggestions?  Thank you!