> Hm, but especially :25 was traditionally used by MUAs, no? > Who used the submission port ~a decade ago?
User agents. I'm pretty sure submission was a thing _two_ decades ago, though IIRC not all that big a thing. (Mind you, it may not have been on the port it's on today, but there was something SMTPish that was designed for MUA submissions, on a separate port.) /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B