Actually, call waiting works for me. Whenever I am on a call and someone else calls, I hear a beep and I can see on the screen that I have another call. If I don't answer, the other call stays in my call history as an unanswered call.
About the first issue, I wondered about that too. I had a really dumb Sony Ericsson phone which supported this feature.
P.S. I misread your call waiting issue... Whenever I call someone who has call waiting I get a beep that tells me I am waiting... However, as far as I know this is an operator feature. On another operator a voice actually tells you to wait because the other party is talking.