--- cyrus-imapd-2.3.8/imap/sync_client.c	2007-01-09 12:29:30.000000000 -0500
+++ cyrus-imapd-2.3.8+/imap/sync_client.c	2007-04-10 16:15:06.000000000 -0400
@@ -61,6 +61,8 @@
 #include <errno.h>
 #include <ctype.h>
 
+#include <netinet/tcp.h>
+
 #include "global.h"
 #include "assert.h"
 #include "mboxlist.h"
@@ -3191,6 +3193,20 @@
 	_exit(1);
     }
 
+    {
+	struct protoent	*proto;
+	int		one = 1;
+
+	if (( proto = getprotobyname( "tcp" )) != NULL ) {
+	    if ( setsockopt( be->sock, proto->p_proto, TCP_NODELAY,
+		    &one, sizeof( one )) != 0 ) {
+		perror( "setsockopt TCP_NODELAY" );
+	    }
+	} else {
+	    perror( "getprotobyname tcp" );
+	}
+    }
+
     return be;
 }
 
--- cyrus-imapd-2.3.8/imap/sync_server.c	2006-11-30 12:11:20.000000000 -0500
+++ cyrus-imapd-2.3.8+/imap/sync_server.c	2007-04-10 16:15:31.000000000 -0400
@@ -63,6 +63,7 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <netinet/in.h>
+#include <netinet/tcp.h>
 #include <arpa/inet.h>
 #include <ctype.h>
 
@@ -375,6 +376,20 @@
     sync_in = prot_new(0, 0);
     sync_out = prot_new(1, 1);
 
+    {
+	struct protoent	*proto;
+	int		one = 1;
+
+	if (( proto = getprotobyname( "tcp" )) != NULL ) {
+	    if ( setsockopt( 1, proto->p_proto, TCP_NODELAY,
+		    &one, sizeof( one )) != 0 ) {
+		syslog( LOG_ERR, "setsockopt TCP_NODELAY: %m" );
+	    }
+	} else {
+	    syslog( LOG_ERR, "getprotobyname tcp: %m" );
+	}
+    }
+
     /* Find out name of client host */
     salen = sizeof(sync_remoteaddr);
     if (getpeername(0, (struct sockaddr *)&sync_remoteaddr, &salen) == 0 &&