In this Video you will see how to configure "Bonjour Gateway with Cisco Wireless LAN Controller (WLC) release 7.4".
Cisco 5500 Series Wireless Controllers - Configuration Guides
Bonjour Deployment Guide for 7.4
http://www.cisco.com/en/US/docs/wireless/technology/bonjour/Bonjour_DG_Guide.pdf
Also, starting IOS 6.1 apple has changed the mdns service string for airplay.
Please make sure Appletv and Airtunes services are checked for the clients.