[Mimedefang] some spam not being filtered (2)

[Keith Dowell]

ok see more now what the problem is... getting some spam through - but in
the headers I see all of the headers for sa, but nothing for md (i.e. no
"X-Scanned-By")

the question is, is there a limited number of connections by default (or
instances) that are run, and if too much mail comes in at one time, can it
overrun that default setting.... and is there a way to adjust this?