>I am trying to develop CSTA interface. I am curious how compliant with CSTA you are planning to be eg in the ECMA-218 http://www.ecma-international.org/publications/files/ecma-st/ECMA-218.pdf There is check list starting on pdf pages 173-223 is appendix A5-A12 ? That sees to a huge amount of work to be compliant ..:)