I can think of two products that would suit your needs. One is by P&S ( http://www.passandseymour.com/whatsnew/pdf/cat5_intercom.pdf#search=%22P%26S%20intercom%20systems%20cat%205%22 ),and the other is product called Compoint manufactured by a comapny called Russound ( http://www.russound.com/compoint.htm ).
Hope this helps.
[This message has been edited by A-V Pro (edited 09-17-2006).]
