diff --git a/ChangeLog b/ChangeLog
index a6b1ee8fa..3b9dd2f2c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -17,6 +17,9 @@
       sftp-glob.h sftp-int.c sftp-server.c sftp.c ssh-keygen.c sshconnect.c 
       sshconnect2.c sshd.c]
      fix whitespace: unexpand + trailing spaces.
+   - markus@cvs.openbsd.org 2001/04/05 11:09:17
+     [clientloop.c compat.c compat.h]
+     add SSH_BUG_NOREKEY and detect broken (=all old) openssh versions.
 
 20010405
  - OpenBSD CVS Sync                                              
@@ -4889,4 +4892,4 @@
  - Wrote replacements for strlcpy and mkdtemp
  - Released 1.0pre1
 
-$Id: ChangeLog,v 1.1067 2001/04/05 23:26:32 mouring Exp $
+$Id: ChangeLog,v 1.1068 2001/04/05 23:28:36 mouring Exp $
diff --git a/clientloop.c b/clientloop.c
index 71eda80e6..41920e0f3 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -59,7 +59,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: clientloop.c,v 1.57 2001/04/05 10:42:49 markus Exp $");
+RCSID("$OpenBSD: clientloop.c,v 1.58 2001/04/05 11:09:15 markus Exp $");
 
 #include "ssh.h"
 #include "ssh1.h"
@@ -554,7 +554,7 @@ process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
 				continue;
 
 			case 'R':
-				if (compat20)
+				if (compat20 && !(datafellows && SSH_BUG_NOREKEY))
 					need_rekeying = 1;
 				continue;
 
diff --git a/compat.c b/compat.c
index 85446999a..f96a6c63c 100644
--- a/compat.c
+++ b/compat.c
@@ -23,7 +23,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: compat.c,v 1.44 2001/04/05 10:00:06 markus Exp $");
+RCSID("$OpenBSD: compat.c,v 1.45 2001/04/05 11:09:16 markus Exp $");
 
 #ifdef HAVE_LIBPCRE
 #  include <pcreposix.h>
@@ -69,14 +69,18 @@ compat_datafellows(const char *version)
 	} check[] = {
 		{ "^OpenSSH[-_]2\\.[012]",
 					SSH_OLD_SESSIONID|SSH_BUG_BANNER|
-					SSH_OLD_DHGEX },
+					SSH_OLD_DHGEX|SSH_BUG_NOREKEY },
 		{ "^OpenSSH_2\\.3\\.0", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
-					SSH_OLD_DHGEX},
-		{ "^OpenSSH_2\\.3\\.",  SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX},
+					SSH_OLD_DHGEX|SSH_BUG_NOREKEY},
+		{ "^OpenSSH_2\\.3\\.",  SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
+					SSH_BUG_NOREKEY},
 		{ "^OpenSSH_2\\.5\\.[01]p1",
-					SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX },
+					SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
+					SSH_BUG_NOREKEY },
 		{ "^OpenSSH_2\\.5\\.[012]",
-					SSH_OLD_DHGEX },
+					SSH_OLD_DHGEX|SSH_BUG_NOREKEY },
+		{ "^OpenSSH_2\\.5\\.3",
+					SSH_BUG_NOREKEY },
 		{ "^OpenSSH",		0 },
 		{ "MindTerm",		0 },
 		{ "^2\\.1\\.0",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
diff --git a/compat.h b/compat.h
index e4ca5c1bc..244cd1aa7 100644
--- a/compat.h
+++ b/compat.h
@@ -21,7 +21,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-/* RCSID("$OpenBSD: compat.h,v 1.21 2001/03/27 17:46:49 provos Exp $"); */
+/* RCSID("$OpenBSD: compat.h,v 1.22 2001/04/05 11:09:17 markus Exp $"); */
 
 #ifndef COMPAT_H
 #define COMPAT_H
@@ -46,6 +46,7 @@
 #define SSH_BUG_BIGENDIANAES	0x1000
 #define SSH_BUG_RSASIGMD5	0x2000
 #define SSH_OLD_DHGEX		0x4000
+#define SSH_BUG_NOREKEY		0x8000
 
 void    enable_compat13(void);
 void    enable_compat20(void);