diff --git a/configure.ac b/configure.ac
index 8b58835..074f22f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -131,12 +131,12 @@ fi
 
 # Delayed-ack feature support (experimental).
 AC_ARG_ENABLE(delayed_ack,
-	AS_HELP_STRING([--enable-delayed-ack],[queues multiple DHCPACK replies (default is no)]))
-if test "$enable_delayed_ack" = "yes"; then
+	AS_HELP_STRING([--enable-delayed-ack],[queues multiple DHCPACK replies (default is yes)]))
+# Delayed-ack is on by default, so define if it is not explicitly disabled.
+if test "$enable_delayed_ack" != "no"; then
+    enable_delayed_ack="yes"
 	AC_DEFINE([DELAYED_ACK], [1],
 		  [Define to queue multiple DHCPACK replies per fsync.])
-else
-    enable_delayed_ack="no"
 fi
 
 # DHCPv6 optional compile-time feature.
diff --git a/includes/dhcpd.h b/includes/dhcpd.h
index d149792..a37f550 100644
--- a/includes/dhcpd.h
+++ b/includes/dhcpd.h
@@ -804,7 +804,7 @@ struct lease_state {
 #endif
 
 #if !defined (DEFAULT_DELAYED_ACK)
-# define DEFAULT_DELAYED_ACK 28  /* default SO_SNDBUF size / 576 bytes */
+# define DEFAULT_DELAYED_ACK 0
 #endif
 
 #if !defined (DEFAULT_ACK_DELAY_SECS)
diff --git a/server/dhcp.c b/server/dhcp.c
index a823a4e..765cf8b 100644
--- a/server/dhcp.c
+++ b/server/dhcp.c
@@ -3536,7 +3536,7 @@ void ack_lease (packet, lease, offer, when, msg, ms_nulltp, hp)
 	} else {
   		lease->cltt = cur_time;
 #if defined(DELAYED_ACK) && !defined(DHCP4o6)
-		if (enqueue)
+		if (enqueue && max_outstanding_acks != 0)
 			delayed_ack_enqueue(lease);
 		else 
 #endif
diff --git a/server/dhcpd.conf.5 b/server/dhcpd.conf.5
index 9c99676..e051b99 100644
--- a/server/dhcpd.conf.5
+++ b/server/dhcpd.conf.5
@@ -2118,24 +2118,25 @@ statements
 .B max-ack-delay \fImicroseconds\fR\fB;\fR
 .PP
 .I Count
-should be an integer value from zero to 2^16-1, and defaults to 28.  The
-count represents how many DHCPv4 replies maximum will be queued pending
-transmission until after a database commit event.  If this number is
-reached, a database commit event (commonly resulting in fsync() and
-representing a performance penalty) will be made, and the reply packets
-will be transmitted in a batch afterwards.  This preserves the RFC2131
-direction that "stable storage" be updated prior to replying to clients.
-Should the DHCPv4 sockets "go dry" (select() returns immediately with no
-read sockets), the commit is made and any queued packets are transmitted.
+should be an integer value from zero to 2^16-1 and defaults to 0, which means
+that the feature is disabled.  Otherwise, 28 may be a sensible starting point
+for many configurations (SO_SNDBUF size / 576 bytes.)  The count represents how
+many DHCPv4 replies maximum will be queued pending transmission until after a
+database commit event.  If this number is reached, a database commit event
+(commonly resulting in fsync() and representing a performance penalty) will be
+made, and the reply packets will be transmitted in a batch afterwards.  This
+preserves the RFC2131 direction that "stable storage" be updated prior to
+replying to clients.  Should the DHCPv4 sockets "go dry" (select() returns
+immediately with no read sockets), the commit is made and any queued packets
+are transmitted.
 .PP
 Similarly, \fImicroseconds\fR indicates how many microseconds are permitted
 to pass inbetween queuing a packet pending an fsync, and performing the
 fsync.  Valid values range from 0 to 2^32-1, and defaults to 250,000 (1/4 of
 a second).
 .PP
-Please note that as delayed-ack is currently experimental, the delayed-ack
-feature is not compiled in by default, but must be enabled at compile time
-with \'./configure --enable-delayed-ack\'.
+Please note that delayed-ack is currently experimental so you should test
+carefully before enabling this feature.
 .RE
 .PP
 The