diff --git a/source3/script/tests/test_smbclient_encryption_off.sh b/source3/script/tests/test_smbclient_encryption_off.sh
new file mode 100755
index 00000000000..467a4ee4ced
--- /dev/null
+++ b/source3/script/tests/test_smbclient_encryption_off.sh
@@ -0,0 +1,65 @@
+#!/bin/sh
+
+if [ $# -lt 4 ]; then
+cat <<EOF
+Usage: test_smbclient_encryption_off.sh USERNAME PASSWORD SERVER SMBCLIENT
+EOF
+exit 1;
+fi
+
+USERNAME="$1"
+PASSWORD="$2"
+SERVER="$3"
+SMBCLIENT="$VALGRIND $4"
+
+incdir=`dirname $0`/../../../testprogs/blackbox
+. $incdir/subunit.sh
+
+failed=0
+
+#
+# Let me introduce you to the shares used in this test:
+#
+# "tmp" has the default "smb encrypt" (which is "enabled")
+# "tmpenc" has "smb encrypt = required"
+# "enc_desired" has "smb encrypt = desired"
+#
+
+# Unencrypted connections should work of course, let's test em to be sure...
+
+# SMB1
+testit "smbclient //$SERVER/enc_desired" $SMBCLIENT -U $USERNAME%$PASSWORD //$SERVER/enc_desired -c quit || failed=`expr $failed + 1`
+testit "smbclient //$SERVER/tmp" $SMBCLIENT -U $USERNAME%$PASSWORD //$SERVER/tmp -c quit || failed=`expr $failed + 1`
+# SMB3_02
+testit "smbclient -m smb3_02 //$SERVER/enc_desired" $SMBCLIENT -m smb3_02 -U $USERNAME%$PASSWORD //$SERVER/enc_desired -c quit || failed=`expr $failed + 1`
+testit "smbclient -m smb3_02 //$SERVER/tmp" $SMBCLIENT -m smb3_02 -U $USERNAME%$PASSWORD //$SERVER/tmp -c quit || failed=`expr $failed + 1`
+# SMB3_11
+testit "smbclient -m smb3_11 //$SERVER/enc_desired" $SMBCLIENT -m smb3_11 -U $USERNAME%$PASSWORD //$SERVER/enc_desired -c quit || failed=`expr $failed + 1`
+testit "smbclient -m smb3_11 //$SERVER/tmp" $SMBCLIENT -m smb3_11 -U $USERNAME%$PASSWORD //$SERVER/tmp -c quit || failed=`expr $failed + 1`
+
+# These tests must fail, as encryption is globally off and in combination with "smb
+# encrypt=required" on the share "tmpenc" the server *must* reject the tcon.
+
+# SMB1
+testit_expect_failure "smbclient //$SERVER/tmpenc" $SMBCLIENT -U $USERNAME%$PASSWORD //$SERVER/tmpenc -c quit && failed=`expr $failed + 1`
+testit_expect_failure "smbclient -e //$SERVER/tmpenc" $SMBCLIENT -e -U $USERNAME%$PASSWORD //$SERVER/tmpenc -c quit && failed=`expr $failed + 1`
+# SMB3_02
+testit_expect_failure "smbclient -m smb3_02 //$SERVER/tmpenc" $SMBCLIENT -m smb3_02 -U $USERNAME%$PASSWORD //$SERVER/tmpenc -c quit && failed=`expr $failed + 1`
+testit_expect_failure "smbclient -e -m smb3_02 //$SERVER/tmpenc" $SMBCLIENT -e -m smb3_02 -U $USERNAME%$PASSWORD //$SERVER/tmpenc -c quit && failed=`expr $failed + 1`
+# SMB3_11
+testit_expect_failure "smbclient -m smb3_11 //$SERVER/tmpenc" $SMBCLIENT -m smb3_11 -U $USERNAME%$PASSWORD //$SERVER/tmpenc -c quit && failed=`expr $failed + 1`
+testit_expect_failure "smbclient -e -m smb3_11 //$SERVER/tmpenc" $SMBCLIENT -e -m smb3_11 -U $USERNAME%$PASSWORD //$SERVER/tmpenc -c quit && failed=`expr $failed + 1`
+
+# These tests must fail, as the client requires encryption and it's off on the server
+
+# SMB1
+testit_expect_failure "smbclient -e //$SERVER/enc_desired" $SMBCLIENT -e -U $USERNAME%$PASSWORD //$SERVER/enc_desired -c quit && failed=`expr $failed + 1`
+testit_expect_failure "smbclient -e //$SERVER/tmp" $SMBCLIENT -e -U $USERNAME%$PASSWORD //$SERVER/tmp -c quit && failed=`expr $failed + 1`
+# SMB3_02
+testit_expect_failure "smbclient -e -m smb3_02 //$SERVER/enc_desired" $SMBCLIENT -e -m smb3_02 -U $USERNAME%$PASSWORD //$SERVER/enc_desired -c quit && failed=`expr $failed + 1`
+testit_expect_failure "smbclient -e -m smb3_02 //$SERVER/tmp" $SMBCLIENT -e -m smb3_02 -U $USERNAME%$PASSWORD //$SERVER/tmp -c quit && failed=`expr $failed + 1`
+# SMB3_11
+testit_expect_failure "smbclient -e -m smb3_11 //$SERVER/enc_desired" $SMBCLIENT -e -m smb3_11 -U $USERNAME%$PASSWORD //$SERVER/enc_desired -c quit && failed=`expr $failed + 1`
+testit_expect_failure "smbclient -e -m smb3_11 //$SERVER/tmp" $SMBCLIENT -e -m smb3_11 -U $USERNAME%$PASSWORD //$SERVER/tmp -c quit && failed=`expr $failed + 1`
+
+testok $0 $failed
diff --git a/source3/selftest/tests.py b/source3/selftest/tests.py
index d80750ec162..4d427ed6eeb 100755
--- a/source3/selftest/tests.py
+++ b/source3/selftest/tests.py
@@ -483,6 +483,11 @@ plantestsuite("samba3.blackbox.rpcclient.pw-nt-hash", "simpleserver",
                "$USERNAME", "$PASSWORD", "$SERVER",
                os.path.join(bindir(), "rpcclient")])
 
+plantestsuite("samba3.blackbox.smbclient.encryption_off", "simpleserver",
+              [os.path.join(samba3srcdir, "script/tests/test_smbclient_encryption_off.sh"),
+               "$USERNAME", "$PASSWORD", "$SERVER",
+               smbclient3])
+
 options_list = ["", "-e"]
 for options in options_list:
     plantestsuite("samba3.blackbox.smbclient_krb5 old ccache %s" % options, "ktest:local",