Long ago, I was looking for a solution to lock/unlock cisco ip phones keypads, without using EM, but couldn't find one free of cost, and tried to develop own and finally have resolved the mystry.
Please drop me an email if somebody needs the source codes, you can develop solution to lock/unlock cisco IP phones keypad by integration of applications developed using TAPI, C++, .NET, C#, Java, JSP and Cisco IP Phone XML services.
You will need different tools including Micrsoft Visual Studio, NetBeans IDE, VC++6.0, and sun web server for JSP pages which will push the xml to ip phones.
This would for as many number of ip phones as you wish and will work on all Cisco call and unified communication managers versions (i.e. 4.X, 5.X, 6.x).
Please let me know if anybody needs source codes for reference, but it should be used as sample application for a reference only and should not be assumed finalised product.
Thanks & Regards,
M. Mudassir Saeed