It's a major bug if interoperability is screwed. It is.
I have received MIME messages that I cannot handle because there are unquoted
dots in parameters. I am pretty sure MetaMail is among the culprits. My
users are unsympathetic when I tell them I'm obeying the spec and the sending
mailer is not. The bug reports are coming in and I have to do something. I
don't think I can wait for the draft standard.
If I delete dot from my tspecials, then I will generate non-conforming MIME
and what's worse my new code couldn't talk to my old code. That's even less
I'm afraid this mistake in MIME has forced me into a corner. I need to split
tspecials into two groups, one for what I generate, one for what I parse, the
difference being that the latter omits dot. I suspect that other implementors
will have the same problem, so we may end up having to put it into MIME.