Call to external number

If I create a custom extension with a custom technology dial to external number, and disble call waiting, additional calls will still get sent through. If I create a follow-me to external number tied to a SIP extension with 0 initial ring and call waiting disabled, additional calls still get sent through.

Secondly, I can’t get confirm calls to work when using a custom device extension.

Are these bugs or features I am not using correctly.

I need to keep to 1 call per external number entry with call confim.