diff -Naur courier-0.64.0/courier/module.esmtp/courieresmtpd.c courier-0.64.0-1/courier/module.esmtp/courieresmtpd.c
--- courier-0.64.0/courier/module.esmtp/courieresmtpd.c	2009-08-23 12:26:34.000000000 +0200
+++ courier-0.64.0-1/courier/module.esmtp/courieresmtpd.c	2010-01-31 19:46:52.000000000 +0100
@@ -81,10 +81,14 @@
 
 static void tarpit()
 {
-	sleep(teergrube);
-	teergrube *= 2;
-	if (teergrube > MAX_TEERGRUBE)
-		teergrube=MAX_TEERGRUBE;
+	const char *p;
+	if ((p=getenv("TARPIT")) && atoi(p))
+	{
+		sleep(teergrube);
+		teergrube *= 2;
+		if (teergrube > MAX_TEERGRUBE)
+			teergrube=MAX_TEERGRUBE;
+	}
 }
 
 void iov_logerror(const char *q, const char *p)
diff -Naur courier-0.64.0/courier/module.esmtp/esmtpd.dist.in courier-0.64.0-1/courier/module.esmtp/esmtpd.dist.in
--- courier-0.64.0/courier/module.esmtp/esmtpd.dist.in	2009-08-13 00:25:49.000000000 +0200
+++ courier-0.64.0-1/courier/module.esmtp/esmtpd.dist.in	2010-01-31 19:41:17.000000000 +0100
@@ -51,6 +51,12 @@
 
 BOFHNOVRFY=0
 
+##NAME: TARPIT:1
+#
+#  Set TARPIT to 0 to disable tarpitting
+
+TARPIT=1
+
 ##NAME: NOADDMSGID:0
 #
 #  The following environment variables keep Courier from adding
diff -Naur courier-0.64.0/courier/module.esmtp/esmtpd-ssl.dist.in courier-0.64.0-1/courier/module.esmtp/esmtpd-ssl.dist.in
--- courier-0.64.0/courier/module.esmtp/esmtpd-ssl.dist.in	2009-08-13 00:25:49.000000000 +0200
+++ courier-0.64.0-1/courier/module.esmtp/esmtpd-ssl.dist.in	2010-01-31 19:41:49.000000000 +0100
@@ -44,6 +44,12 @@
 
 BOFHNOVRFY=0
 
+##NAME: TARPIT:1
+#
+#  Set TARPIT to 0 to disable tarpitting
+
+TARPIT=1
+
 ##NAME: NOADDMSGID:0
 #
 #  The following environment variables keep Courier from adding