I've just received an "ezmlm warning" from the Subversion mailing list saying:
"m1234567" wasn't the original name -- I've changed that. And obviously, MYDOMAIN was actually, my domain name!
The fact that the mail arrived in the end presumably shows that they fixed it.... but clearly some messages have been bounced, which isn't too clever really. It was broken at some point and this error has not been reported on the DH status page.