Index: Modules/socketmodule.c
===================================================================
--- Modules/socketmodule.c	(revision 80433)
+++ Modules/socketmodule.c	(working copy)
@@ -2224,8 +2224,10 @@
 	if (backlog == -1 && PyErr_Occurred())
 		return NULL;
 	Py_BEGIN_ALLOW_THREADS
-	if (backlog < 1)
-		backlog = 1;
+	/* To avoid problems on systems that don't allow a negative backlog
+	 * (which doesn't make sense anyway) we force a minimum value of 0. */
+	if (backlog < 0)
+		backlog = 0;
 	res = listen(s->sock_fd, backlog);
 	Py_END_ALLOW_THREADS
 	if (res < 0)