diff -urN 2.2.10/include/linux/sysctl.h 2.2.10-MPI/include/linux/sysctl.h
--- 2.2.10/include/linux/sysctl.h	Tue Jul 13 00:33:04 1999
+++ 2.2.10-MPI/include/linux/sysctl.h	Thu Jul 22 12:15:11 1999
@@ -223,7 +223,8 @@
 	NET_IPV4_ICMP_PARAMPROB_RATE=62,
 	NET_IPV4_ICMP_ECHOREPLY_RATE=63,
 	NET_IPV4_ICMP_IGNORE_BOGUS_ERROR_RESPONSES=64,
-	NET_IPV4_IGMP_MAX_MEMBERSHIPS=65
+	NET_IPV4_IGMP_MAX_MEMBERSHIPS=65,
+	NET_IPV4_TCP_DISABLE_DELACKS=66,
 };
 
 enum {
diff -urN 2.2.10/net/ipv4/sysctl_net_ipv4.c 2.2.10-MPI/net/ipv4/sysctl_net_ipv4.c
--- 2.2.10/net/ipv4/sysctl_net_ipv4.c	Mon Jan 18 02:27:54 1999
+++ 2.2.10-MPI/net/ipv4/sysctl_net_ipv4.c	Thu Jul 22 12:15:11 1999
@@ -60,6 +60,7 @@
 extern int sysctl_tcp_rfc1337;
 extern int sysctl_tcp_syn_taildrop; 
 extern int sysctl_max_syn_backlog; 
+extern int sysctl_tcp_disable_delacks;
 
 /* From icmp.c */
 extern int sysctl_icmp_destunreach_time;
@@ -184,6 +185,8 @@
 	{NET_IPV4_IGMP_MAX_MEMBERSHIPS, "igmp_max_memberships",
 	 &sysctl_igmp_max_memberships, sizeof(int), 0644, NULL, &proc_dointvec},
 #endif
+	{NET_IPV4_TCP_DISABLE_DELACKS, "tcp_disable_delacks",
+	 &sysctl_tcp_disable_delacks, sizeof(int), 0644, NULL, &proc_dointvec},
 	{0}
 };
 
diff -urN 2.2.10/net/ipv4/tcp_input.c 2.2.10-MPI/net/ipv4/tcp_input.c
--- 2.2.10/net/ipv4/tcp_input.c	Tue Jul 13 00:33:23 1999
+++ 2.2.10-MPI/net/ipv4/tcp_input.c	Thu Jul 22 12:18:31 1999
@@ -82,6 +82,8 @@
 int sysctl_tcp_stdurg;
 int sysctl_tcp_rfc1337;
 
+int sysctl_tcp_disable_delacks;
+
 static int prune_queue(struct sock *sk);
 
 /* There is something which you must keep in mind when you analyze the
@@ -1603,7 +1605,9 @@
 	    /* We entered "quick ACK" mode or... */
 	    tcp_in_quickack_mode(tp) ||
 	    /* We have out of order data */
-	    (skb_peek(&tp->out_of_order_queue) != NULL)) {
+	    (skb_peek(&tp->out_of_order_queue) != NULL) ||
+	    /* we are allowed to disable the delacks and TCP_NODELAY is set */
+	    (sysctl_tcp_disable_delacks && sk->nonagle == 1)) {
 		/* Then ack it now */
 		tcp_send_ack(sk);
 	} else {