Assigning DHCP address to nodes on different vlans

I have a campus network with a core, distribution and access layer switches. two vlans are configured on on the switches. vlan 2 (192.168.2.1 as management ip for data) and vlan 3 (192.168.3.1 management ip for voice).
The distribution switch (catalyst 3750) is configured with DHCP services (dhcp server) on the network 192.168.2.0. I want to extend the netwrok using wireless devices, which I want to be on vlan 4 (192.168.4.1)for management purpose.

My challenge here is making users accessing the network through the wireless devices (which are on vlan 4)to be able to obtain DHCP address (192.168.2.**) from the distribution switch on the vlan 2 network.

Please someone help me out as this has been challenging for a while now.