My blog is set to require that commenters enter an email address. If I try to leave a comment without an email, I get the standard error message: "ERROR: please fill the required fields (name, email)."
Nevertheless, comments get added on my blog that have blank email addresses. There were 3 today.
Every instance where this has happened was a spam comment. I am assuming that spammers are somehow bypassing the usual edits requiring and email address. I have XML-RPC enabled.
I wanted to post this here for discussion before I report it in the bug system.