Question : dhcp with 2 ip ranges on sbs2003

I have a client running a SBS2003 server with exchange. They have a R&D section which they want to keep separate from the other users. I was thinking of assigning them to a different IP range, this way they will be able to use exchange and still have access to some all share folders. I.e. have the general users on 192.168.0.* and put them on 192.168.10.*. I have a extra NIC in the server and have a extra switch for them. I have added a additional scope to the DHCP, but am not sure this is the only thing to do.  Some advise will do.

Could you maybe give me some guidance please?

Answer : dhcp with 2 ip ranges on sbs2003

I have deciede to go with a VLAN type setup as SBS doesn't seem to like working with 2 subnets. Sorry for the delay and thanks for the advise.