The functionality is available here but as far as I can tell it’s not enabled for the forums. Before we do enable it we probably should have it first send an activation email so that only those with valid working email addresses can use it. When mail bounces our hosting provider blocks that address from getting any further emails. Sometimes mail has bounced and the address is a valid one so I really don’t know what would cause that – odd filters on the receiver’s end perhaps. The blocking is not forever so eventually another mailing attempt is made to the addresses that bounce.
We have to be careful about the bounce rates to avoid looking like a spammer.
One of the downsides of this is also that we can end up being labeled as spam by someone being lazy. As an example, a person registers so they can post something for sale in the classifieds forum. Their item sells and we don’t see or hear from them again. Replies are made to the classified post and notifications (which they chose to receive) are sent to them. Rather than come back and unsubscribe they label the email as spam. As this happens with more and more users we end up having everything labeled as spam – all thanks to laziness.
Email can be such a pain. lol