Apologies if this is a trivial question, I haven't seen it discussed. Searching brought up 1 related issue, which 1) was not answered and 2) was looking at the problem from the wrong side. This was someone wondering how to exclude bounces from the rest that he relayed to his relayhost.
I'm at the other side of the problem. We've got a server that's relayhost for lots of clients of various configurations and sizes. Some of these clients are, in fact, MX-es directly connected to the net, but still use our server as an outgoing relay. Those of them that do delayed bounces, send their backscatter to us. Supposing that we have to relay for them and we can't force them all to stop bouncing, what would be the best solution?
Somehow I don't think that rejecting the null sender is entirely correct. rgds, netcat
