Networking :: DHCP3 Server - Setting Double Range Of IP Address

I would like to set a double range of IP address with my DHCP3-server. Now, I have eth0 (which is my only network card) with this IP address : 172.16.93.1 and I have created a second interface eth0:1 with this address: 192.168.3.1. The goal is to give an IP address 172.16.93.X to phones (with option 66) and the IP address 192.168.3.X to the computers.

This is my DHCPD.conf :
ddns-update-style none;
option domain-name "mycompany.com";
option domain-name-servers 172.16.93.1;
default-lease-time 3600;
max-lease-time 2347200;
authoritative;
log-facility local7;
option ip-forwarding off;
default-lease-time 20;
max-lease-time 20; .....

Right now my DHCP server work fine, (I means, no error at the startup ) but the server give always the same kind of IP address, whatever if it's a phone or a computer. I notice something "wired", if I put the :
subnet 192.168.3.0 netmask 255.255.255.0 {
range 192.168.3.100 192.168.3.199;
option routers 192.168.3.254; }
(Which is first in the dhcpd.conf) after the "subnet 172.16.93.0 netmask 255.255.255.0", the server will give IP address 172.16.93.X at all the clients. Is it possible to give more than one IP range with one network card at the same time? And how set the option 66 to only give IP address (172.16.93.X) to the phones?