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diff --git a/src/mailman/mta/connection.py b/src/mailman/mta/connection.py
new file mode 100644
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+++ b/src/mailman/mta/connection.py
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+# Copyright (C) 2009 by the Free Software Foundation, Inc.
+#
+# This file is part of GNU Mailman.
+#
+# GNU Mailman is free software: you can redistribute it and/or modify it under
+# the terms of the GNU General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option)
+# any later version.
+#
+# GNU Mailman is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.
+
+"""MTA connections."""
+
+from __future__ import absolute_import, unicode_literals
+
+__metaclass__ = type
+__all__ = [
+    'Connection',
+    ]
+
+
+import logging
+import smtplib
+
+from mailman.config import config
+
+
+log = logging.getLogger('mailman.smtp')
+
+
+
+class Connection:
+    """Manage a connection to the SMTP server."""
+    def __init__(self, host, port, sessions_per_connection):
+        """Create a connection manager.
+
+        :param host: The host name of the SMTP server to connect to.
+        :type host: string
+        :param port: The port number of the SMTP server to connect to.
+        :type port: integer
+        :param sessions_per_connection: The number of SMTP sessions per
+            connection to the SMTP server.  After this number of sessions
+            has been reached, the connection is closed and a new one is
+            opened.  Set to zero for an unlimited number of sessions per
+            connection (i.e. your MTA has no limit).
+        :type sessions_per_connection: integer
+        """
+        self._host = host
+        self._port = port
+        self._connections_per_session = sessions_per_connection
+        self._connection = None
+
+    def _connect(self):
+        """Open a new connection."""
+        self._connection = smtplib.SMTP()
+        log.debug('Connecting to %s:%s', self._host, self._port)
+        self._connection.connect(self._host, self._port)
+
+    def sendmail(self, envsender, recips, msgtext):
+        """Mimic `smtplib.SMTP.sendmail`."""
+        if self._connection is None:
+            self._connect()
+        try:
+            results = self._connection.sendmail(envsender, recips, msgtext)
+        except smtplib.SMTPException:
+            # For safety, close this connection.  The next send attempt will
+            # automatically re-open it.  Pass the exception on up.
+            self.quit()
+            raise
+        # This session has been successfully completed.
+        self._sessions_per_connection -= 1
+        # By testing exactly for equality to 0, we automatically handle the
+        # case for SMTP_MAX_SESSIONS_PER_CONNECTION <= 0 meaning never close
+        # the connection.  We won't worry about wraparound <wink>.
+        if self._sessions_per_connection == 0:
+            self.quit()
+        return results
+
+    def quit(self):
+        """Mimic `smtplib.SMTP.quit`."""
+        if self._connection is None:
+            return
+        try:
+            self._connection.quit()
+        except smtplib.SMTPException:
+            pass
+        self._connection = None