Per client DNS server assignment using Pfsense

I have a network where pfsense is the gateway. There are two sets of clients that I want. One where there will be some restrictions to the network (example, IM being blocked) and one network where there are no restrictions.

One easy way I thought about doing this was assigning the different domains different DNS servers. One set could use OpenDNS, the other could use Google's Public DNS. The set with OpenDNS would have the filter options on (using OpenDNS' dashboard, I can check block IM .... so I do not manually need to block login.oscar.aol.com, meebo.com, gmail chat ....etc).

So the problem is the DHCP server looks like it will only assign a single set of DNS servers to clients. Is there a way to set a per client assignment?

Is there a better way to obtain what I want to obtain. This is just a small home network. I do not need anything fancy, but I do need this functionality in one way or another.

From serverfault Trix

• You can use the Captive Portal functionality of pfSense to force authentication, and then adjust the settings by user. It can be setup to use RADIUS to authenticate against AD.

  From tomjedrz