diff --git a/scripts/dhcp-discover.nse b/scripts/dhcp-discover.nse
index 25f4b3623..ec640c8d2 100644
--- a/scripts/dhcp-discover.nse
+++ b/scripts/dhcp-discover.nse
@@ -67,7 +67,14 @@ require 'shortport'
 require 'stdnse'
 
 -- We want to run against a specific host if UDP/67 is open
-portrule = shortport.portnumber(67, "udp")
+function portrule(host, port)
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only.", SCRIPT_NAME)
+		return false
+	end
+
+	return shortport.portnumber(67, "udp")(host, port)
+end
 
 -- We will want to run as a prerule any time
 --prerule  = function()
diff --git a/scripts/firewalk.nse b/scripts/firewalk.nse
index ddf359144..edca1b5c6 100644
--- a/scripts/firewalk.nse
+++ b/scripts/firewalk.nse
@@ -57,7 +57,9 @@ firewalk tool.
 --
 
 
--- 12/29/2010: initial version
+-- 11/29/2010: initial version
+-- 03/28/2011: added IPv4 check
+
 author = "Henri Doreau"
 
 license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
@@ -422,6 +424,11 @@ hostrule = function(host)
     return false
   end
 
+  if nmap.address_family() ~= 'inet' then
+    stdnse.print_debug("%s is IPv4 compatible only.", SCRIPT_NAME)
+    return false
+  end
+
   if not host.interface then
     return false
   end
diff --git a/scripts/ipidseq.nse b/scripts/ipidseq.nse
index c97272a1f..b79040564 100644
--- a/scripts/ipidseq.nse
+++ b/scripts/ipidseq.nse
@@ -30,6 +30,7 @@ categories = {"safe", "discovery"}
 
 require 'bin'
 require 'packet'
+require 'nmap'
 require 'stdnse'
 
 local NUMPROBES = 6
@@ -198,6 +199,10 @@ hostrule = function(host)
 		end
 		return false
 	end
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only.", SCRIPT_NAME)
+		return false
+	end
 	if not host.interface then
 		return false
 	end
diff --git a/scripts/path-mtu.nse b/scripts/path-mtu.nse
index 8687010ad..db4a4cd9b 100644
--- a/scripts/path-mtu.nse
+++ b/scripts/path-mtu.nse
@@ -38,6 +38,7 @@ categories = {"safe", "discovery"}
 
 require 'bin'
 require 'packet'
+require 'nmap'
 require 'stdnse'
 
 local IPPROTO_ICMP = packet.IPPROTO_ICMP
@@ -279,6 +280,10 @@ hostrule = function(host)
 		end
 		return false
 	end
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only.", SCRIPT_NAME)
+		return false
+	end
 	if not (host.interface and host.interface_mtu) then
 		return false
 	end
diff --git a/scripts/qscan.nse b/scripts/qscan.nse
index 950e88d0f..a5272bf4c 100644
--- a/scripts/qscan.nse
+++ b/scripts/qscan.nse
@@ -53,6 +53,7 @@ require 'stdnse'
 require 'bin'
 require 'packet'
 require 'tab'
+require 'nmap'
 
 -- defaults
 local DELAY = 0.200
@@ -378,6 +379,10 @@ hostrule = function(host)
 		end
 		return false
 	end
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only.", SCRIPT_NAME)
+		return false
+	end
 	if not host.interface then
 		return false
 	end
diff --git a/scripts/sniffer-detect.nse b/scripts/sniffer-detect.nse
index c97ac3d88..d3b336d1a 100644
--- a/scripts/sniffer-detect.nse
+++ b/scripts/sniffer-detect.nse
@@ -17,6 +17,10 @@ categories = {"discovery", "intrusive"}
 
 -- okay, we're interested only in hosts that are on our ethernet lan
 hostrule = function(host)
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only.", SCRIPT_NAME)
+		return false
+	end
 	return host.directly_connected == true and
 		host.mac_addr ~= nil and
 		host.mac_addr_src ~= nil and