Something appears wrong with the 'Reply' facility in Web Mail. Instead of the sender's address appearing in the 'To:' field, the user's own address appears. This means that unless the user notices it, mail will presumably simply bounce back and not go to the person to whom the reply was intended. I must admit I never thought to try it -- I just altered the 'To:' field to the correct address.
This is a new thing; must have happened within the last day or so, and applies to people on PlusNet as well, and presumably to Force9 etc.
I first noticed it when I tried to use WebMail this morning, and I'm amazed the anomaly is still there -- I can't believe that it's a fault on my computer, but on the other hand no one else seems to have noticed, so perhaps it's just me...?