I don't recall that issue being raised before, so I suspect the answer is no. You may want to suggest it , as an option, in...http://3cx.ideascale.com/
In most jurisdictions, I believe, that it is only necessary that one party, in the conversation , be aware that it is being recorded, or, that a message informing the caller , like, "calls may be recorded for training purposes" is played to them, usually while in a queue.