Dell Powerconnect 28xx series Multiple DNS servers

Hey,

Hey i have a Dell Powerconnect 2824 series switch and i am setting up the switch as a dhcp server for the client pc's. I want the dhcp server to assign two dns servers, one primary and a secondary dns ip. 

So basically the first dns ip would be 192.168.1.9

and the secondary dns ip is 192.168.1.10

but i cant find this setting in the switch web management console.  I can only assign a single dns ip.