first make sure you have enabled routing on the 2610, use the ip routing command, and then make sure that the clients default gateway is the ip of the particular vlan it is on. That should do the trick for you. So if host A is on the 172 vlan, the host's gateway should point to that 172 vlan IP, and the host's on the 10 network should have their gateways point to the 10 vlan ip address.