diff --git a/Shorewall2/changelog.txt b/Shorewall2/changelog.txt
index e6fffdcec..2d2fc6db4 100644
--- a/Shorewall2/changelog.txt
+++ b/Shorewall2/changelog.txt
@@ -106,3 +106,5 @@ Changes since 2.0.3
 50) Add a clarification and fix a typo in the blacklist file.
 
 51) Allow setting a specify MSS value.
+
+52) Detect duplicate zone names.
diff --git a/Shorewall2/firewall b/Shorewall2/firewall
index 36bef0c20..3465a03d6 100755
--- a/Shorewall2/firewall
+++ b/Shorewall2/firewall
@@ -765,6 +765,17 @@ find_hosts() # $1 = host zone
     done < $TMP_DIR/hosts
 }
 
+#
+# Check for duplicate zone definitions
+#
+check_duplicate_zones() {
+    local localzones=
+
+    for zone in $zones; do
+	list_search $zone $localzones && startup_error "Zone $zone is defined more than once"
+	localzones="$localzones $zone"
+    done
+}
 #
 # Determine the interfaces on the firewall
 #
@@ -2631,6 +2642,7 @@ check_config() {
     echo "Determining Zones..."
 
     determine_zones
+    check_dupliate_zones
 
     [ -z "$zones" ] && startup_error "ERROR: No Zones Defined"
 
@@ -5387,6 +5399,7 @@ initialize_netfilter () {
     echo "Determining Zones..."
 
     determine_zones
+    check_duplicate_zones
 
     [ -z "$zones" ] && startup_error "No Zones Defined"
 
@@ -6112,7 +6125,7 @@ activate_rules()
     # Create forwarding chains for complex zones and generate jumps for IPSEC source hosts to that chain.
     #
     for zone in $zones; do
-	if eval test -n \$${zone}_is_complex ; then
+	if eval test -n \"\$${zone}_is_complex\" ; then
 	    frwd_chain=${zone}_frwd
 	    createchain $frwd_chain No
 
diff --git a/Shorewall2/releasenotes.txt b/Shorewall2/releasenotes.txt
index c122e12df..2d0cb02a6 100755
--- a/Shorewall2/releasenotes.txt
+++ b/Shorewall2/releasenotes.txt
@@ -1,4 +1,4 @@
-Shorewall 2.1.11
+Shorewall 2.1.12
 
 ----------------------------------------------------------------------
 Problems Corrected since 2.0.3
@@ -83,6 +83,12 @@ Problems corrected since 2.1.10
 4)  A typo has been corrected in and a clarification added to the
     /etc/shorewall/blacklist file.
 
+Problems corrected since 2.1.11
+
+1)  If a zone name appears more than once in /etc/shorewall/zones,
+    Shorewall will now issue an error message and terminate during
+    "shorewall [re]start" or "shorewall check".
+
 -----------------------------------------------------------------------
 Issues when migrating from Shorewall 2.0 to Shorewall 2.1: