diff --git a/openerp/service/server.py b/openerp/service/server.py
index c3baace20dc..af01ea9d54f 100644
--- a/openerp/service/server.py
+++ b/openerp/service/server.py
@@ -91,9 +91,6 @@ class RequestHandler(werkzeug.serving.WSGIRequestHandler):
         me = threading.currentThread()
         me.name = 'openerp.service.http.request.%s' % (me.ident,)
 
-# _reexec() should set LISTEN_* to avoid connection refused during reload time. It
-# should also work with systemd socket activation. This is currently untested
-# and not yet used.
 
 class ThreadedWSGIServerReloadable(LoggingBaseWSGIServerMixIn, werkzeug.serving.ThreadedWSGIServer):
     """ werkzeug Threaded WSGI Server patched to allow reusing a listen socket
@@ -105,14 +102,15 @@ class ThreadedWSGIServerReloadable(LoggingBaseWSGIServerMixIn, werkzeug.serving.
                                                            handler=RequestHandler)
 
     def server_bind(self):
-        envfd = os.environ.get('LISTEN_FDS')
-        if envfd and os.environ.get('LISTEN_PID') == str(os.getpid()):
+        SD_LISTEN_FDS_START = 3
+        if os.environ.get('LISTEN_FDS') == '1' and os.environ.get('LISTEN_PID') == str(os.getpid()):
             self.reload_socket = True
-            self.socket = socket.fromfd(int(envfd), socket.AF_INET, socket.SOCK_STREAM)
-            # should we os.close(int(envfd)) ? it seem python duplicate the fd.
+            self.socket = socket.fromfd(SD_LISTEN_FDS_START, socket.AF_INET, socket.SOCK_STREAM)
+            _logger.info('HTTP service (werkzeug) running through socket activation')
         else:
             self.reload_socket = False
             super(ThreadedWSGIServerReloadable, self).server_bind()
+            _logger.info('HTTP service (werkzeug) running on %s:%s', self.server_name, self.server_port)
 
     def server_activate(self):
         if not self.reload_socket:
@@ -254,7 +252,6 @@ class ThreadedServer(CommonServer):
         t = threading.Thread(target=self.http_thread, name="openerp.service.httpd")
         t.setDaemon(True)
         t.start()
-        _logger.info('HTTP service (werkzeug) running on %s:%s', self.interface, self.port)
 
     def start(self, stop=False):
         _logger.debug("Setting signal handlers")
@@ -853,7 +850,8 @@ def _reexec(updated_modules=None):
         args += ["-u", ','.join(updated_modules)]
     if not args or args[0] != exe:
         args.insert(0, exe)
-    os.execv(sys.executable, args)
+    # We should keep the LISTEN_* environment variabled in order to support socket activation on reexec
+    os.execve(sys.executable, args, os.environ)
 
 def load_test_file_yml(registry, test_file):
     with registry.cursor() as cr: