[Exim] refused: too many connections

Hello,

I'm upgrading to 4.24 from 4.22 with the following process:

    1.    recreate the Local/Makefile, imitating values of the
        old Makefile (no straight copy)

    2.    make; make install

    3.    copied the old exim symlink to exim.old
        stopped exim through an init.d script
        ln -s exim-4.24-1 exim
        start exim through init.d script

After doing this, mail continued on its way, but I get a lot of the
following errors from the server:

    2003-12-01 15:18:50 Connection from 209.176.254.4 refused: too
    many connections

for various IP addresses, both external and internal. Moving back to
the exim-4.22 alleviates this problem. Here is an example of the same
error from an Exim client:

    2003-12-01 15:18:52 1AQuVQ-0006L1-00 == alice@???
    T=remote_smtp defer (0): SMTP error from remote mailer after
    initial connection: host intrepid.marinar.com [209.176.254.16]:
    421 intrepid.marinar.com: Too many concurrent SMTP connections;
    please try again later.

At the time, exiwhat reported 13 total incoming connections.

Here is my configuration:

    smtp_accept_max = 0

The docs suggest a 421 error is controlled by the
'smtp_accept_max_per_host' setting, however this setting is unset and
the default is zero. Setting it to '100' also exhibits the same
behavior. Please let me know what other configuration may relevant.

Reading the UPDATING docs didn't suggest a solution. I would be
grateful to hear suggestions on how to gather more information about
this problem. In the meantime, I'll continue to search through the
list and changelogs to see what has happened.

thanks,
hank