Index: ipidseq.nse
===================================================================
--- ipidseq.nse	(revision 22788)
+++ ipidseq.nse	(working copy)
@@ -30,6 +30,8 @@
 
 require 'bin'
 require 'packet'
+require 'nmap'
+require 'stdnse'
 
 local NUMPROBES = 6
 
@@ -193,10 +195,14 @@
 		end
 		nmap.registry['ipidseq']['rootfail'] = true
 		if nmap.verbosity() > 0 then
-			nmap.log_write("stdout", "IPIDSEQ: not running for lack of privileges")
+			stdnse.print_debug("%s not running for lack of privileges, abort!", SCRIPT_NAME)
 		end
 		return false
 	end
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only, abort!", SCRIPT_NAME)
+		return false
+	end
 	if not host.interface then
 		return false
 	end
Index: qscan.nse
===================================================================
--- qscan.nse	(revision 22788)
+++ qscan.nse	(working copy)
@@ -53,6 +53,7 @@
 require 'bin'
 require 'packet'
 require 'tab'
+require 'nmap'
 
 -- defaults
 local DELAY = 0.200
@@ -374,10 +375,14 @@
 		end
 		nmap.registry['qscan']['rootfail'] = true
 		if nmap.verbosity() > 0 then
-			nmap.log_write("stdout", "QSCAN: not running for lack of privileges")
+			stdnse.print_debug("%s not running for lack of privileges, abort!", SCRIPT_NAME)
 		end
 		return false
 	end
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only, abort!", SCRIPT_NAME)
+		return false
+	end
 	if not host.interface then
 		return false
 	end
Index: dhcp-discover.nse
===================================================================
--- dhcp-discover.nse	(revision 22788)
+++ dhcp-discover.nse	(working copy)
@@ -148,6 +148,11 @@
 end
 
 action = function(host, port)
+	if(nmap.address_family() ~= 'inet') then
+		stdnse.print_debug("%s is IPv4 compatible only, abort!", SCRIPT_FAMILY)
+		return nil
+	end
+
 	local status, results = go(host, port)
 
 
Index: firewalk.nse
===================================================================
--- firewalk.nse	(revision 22788)
+++ firewalk.nse	(working copy)
@@ -57,7 +57,9 @@
 --
 
 
--- 12/29/2010: initial version
+-- 11/29/2010: initial version
+-- 03/28/2011: added IPv4 check and standized error messages
+
 author = "Henri Doreau"
 
 license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
@@ -416,12 +418,17 @@
     nmap.registry['firewalk']['rootfail'] = true
 
     if nmap.verbosity() > 0 then
-      nmap.log_write("stdout", SCRIPT_NAME .. ": not running for lack of privileges")
+      stdnse.print_debug("%s not running for lack of privileges, abort!", SCRIPT_NAME)
     end
 
     return false
   end
 
+  if nmap.address_family() ~= 'inet' then
+    stdnse.print_debug("%s is IPv4 compatible only, abort!", SCRIPT_NAME)
+    return false
+  end
+
   if not host.interface then
     return false
   end
@@ -468,7 +475,7 @@
     nmap.registry['firewalk']['traceroutefail'] = true
 
     if nmap.verbosity() > 0 then
-      nmap.log_write("stdout", SCRIPT_NAME .. ": requires unavailable traceroute informations")
+      stdnse.print_debug("%s requires unavailable traceroute informations, abort!", SCRIPT_NAME)
     end
 
     return nil
Index: path-mtu.nse
===================================================================
--- path-mtu.nse	(revision 22788)
+++ path-mtu.nse	(working copy)
@@ -38,6 +38,8 @@
 
 require 'bin'
 require 'packet'
+require 'nmap'
+require 'stdnse'
 
 local IPPROTO_ICMP = packet.IPPROTO_ICMP
 local IPPROTO_TCP  = packet.IPPROTO_TCP
@@ -274,10 +276,14 @@
 		end
 		nmap.registry['pathmtu']['rootfail'] = true
 		if nmap.verbosity() > 0 then
-			nmap.log_write("stdout", "PATH-MTU: not running for lack of privileges")
+			stdnse.print_debug("%s not running for lack of privileges, abort!", SCRIPT_NAME)
 		end
 		return false
 	end
+	if nmap.address_family() ~= 'inet' then
+		stdnse.print_debug("%s is IPv4 compatible only, abort!", SCRIPT_NAME)
+		return false
+	end
 	if not (host.interface and host.interface_mtu) then
 		return false
 	end
Index: sniffer-detect.nse
===================================================================
--- sniffer-detect.nse	(revision 22788)
+++ sniffer-detect.nse	(working copy)
@@ -21,7 +21,8 @@
 		host.mac_addr ~= nil and
 		host.mac_addr_src ~= nil and
 		host.interface ~= nil and
-		nmap.get_interface_link(host.interface) == 'ethernet'
+		nmap.get_interface_link(host.interface) == 'ethernet' and
+		nmap.address_family() == 'inet'
 end
 
 local function check (layer2)