diff --git a/nselib/ipOps.lua b/nselib/ipOps.lua
index 9531f64c7..5bcbc32be 100644
--- a/nselib/ipOps.lua
+++ b/nselib/ipOps.lua
@@ -1,3 +1,4 @@
+-- See nmaps COPYING for licence
 module(...,package.seeall)
 
 
diff --git a/nselib/listop.lua b/nselib/listop.lua
index 1f3936782..474c99767 100644
--- a/nselib/listop.lua
+++ b/nselib/listop.lua
@@ -1,3 +1,4 @@
+-- See nmaps COPYING for licence
 module(..., package.seeall)
 
 --[[
diff --git a/nselib/shortport.lua b/nselib/shortport.lua
index 77a06587a..d3d48e1df 100644
--- a/nselib/shortport.lua
+++ b/nselib/shortport.lua
@@ -1,3 +1,4 @@
+-- See nmaps COPYING for licence
 module(..., package.seeall)
 
 portnumber = function(port, _proto, _state)
diff --git a/nselib/stdnse.lua b/nselib/stdnse.lua
index 3a5d13c3d..58b69cc12 100644
--- a/nselib/stdnse.lua
+++ b/nselib/stdnse.lua
@@ -1,3 +1,4 @@
+-- See nmaps COPYING for licence
 module(..., package.seeall)
 
 print_debug = function(...)
@@ -13,17 +14,7 @@ end
 -- separated by the string delimiter (just like in perl)
 -- example: strjoin(", ", {"Anna", "Bob", "Charlie", "Dolores"})
 function strjoin(delimiter, list)
-	local len = getn(list)
-	if len == 0 then 
-		return "" 
-	end
-
-	local string = list[1]
-	for i = 2, len do 
-		string = string .. delimiter .. list[i] 
-	end
-
-	return string
+	return table.concat(list, delimiter);
 end
 
 -- Split text into a list consisting of the strings in text,
@@ -51,47 +42,6 @@ function strsplit(delimiter, text)
 	return list
 end
 
--- String buffer functions. Concatenation is not efficient in 
--- lua as strings are immutable. If a large amount of '..' 
--- operations are needed a string buffer should be used instead
-
---[[
-	local buf = strbuf.new()
-	strbuf.add(buf, 'string') ; strbuf.add(buf, 'data')
-
-	print(buf)                   -- default seperator is a new line
-	print(strbuf.dump(buf))      -- no seperator
-	print(strbuf.dump(buf, ' ')) -- seperated by spaces
-	strbuf.clear(buf)
---]]
-
-strbuf_dump = table.concat 
-
-function strbuf_new()
-	local sbuf = {}
-	sbuf.mt = {}
-	setmetatable(sbuf, sbuf.mt)
-	sbuf.mt.__tostring = function(s) return strbuf_dump(s, '\n') end
-	return sbuf
-end
-
-function strbuf_add(sbuf, s)
-	if not (type(s) == 'string') or
-	   not (type(sbuf) == 'table') then
-		return nil 
-	end
-	table.insert(sbuf, s)
-	return table.getn(sbuf)
-end
-
-function strbuf_clear(sbuf)
-	for i, v in pairs(sbuf) do
-		sbuf[i] = nil
-    	end
-end
-
--- pseudo namespace for string buffers
-strbuf = { new=strbuf_new, add=strbuf_add, dump=strbuf_dump, clear=strbuf_clear }
 
 -- Generic buffer implementation using lexical closures
 --
diff --git a/nselib/strbuf.lua b/nselib/strbuf.lua
new file mode 100644
index 000000000..f7ad014e7
--- /dev/null
+++ b/nselib/strbuf.lua
@@ -0,0 +1,84 @@
+-- license = "See nmaps COPYING for license"
+module("strbuf" ,package.seeall)
+
+-- String buffer functions. Concatenation is not efficient in 
+-- lua as strings are immutable. If a large amount of '..' 
+-- operations are needed a string buffer should be used instead
+
+--[[
+	local buf = strbuf.new()
+	-- from here buf may be used like a string for concatenation operations
+	-- (the lefthand-operand has to be a strbuf, the righthand-operand may be 
+	-- a string or a strbuf)
+	-- alternativly you can assign a value (which will become the first string
+	-- inside the buffer) with new
+	local buf2 = strbuf.new('hello')
+	buf = buf .. 'string'
+	buf = buf .. 'data'
+	print(buf)                   -- default seperator is a new line
+	print(strbuf.dump(buf))      -- no seperator
+	print(strbuf.dump(buf, ' ')) -- seperated by spaces
+	strbuf.clear(buf)
+--]]
+
+
+
+dump = table.concat 
+
+concatbuf =function(sbuf, s)
+	if sbuf == s then
+		error("refusing to concat the same buffer (recursion)!")
+	end
+	if getmetatable(sbuf) ~= mt then
+		error("left-hand operand of the concat operation has to be a strbuf!")
+	end
+	if type(s)=="string" then
+		table.insert(sbuf, s)
+	elseif getmetatable(s) == mt then
+		for _,v in ipairs(s) do
+			table.insert(sbuf, v)
+		end
+	else 
+		error("right-hand operand of concat has to be either string or strbuf!")
+	end
+	return sbuf
+end
+
+local eqbuf = function(sbuf1, sbuf2)
+	if getmetatable(sbuf1) ~= mt then
+		error("equal function expects a value of type strbuf as left-hand operand")
+	end
+	if getmetatable(sbuf1) ~= getmetatable(sbuf2) then
+		return false
+	end
+
+	if #sbuf1 ~= #sbuf2 then
+		return false
+	end
+	
+	for i=1, #sbuf1 do
+		if sbuf1[i] ~= sbuf2[i] then
+			return false
+		end
+	end
+	return true
+end
+clear = function(sbuf)
+	for i, v in pairs(sbuf) do
+		sbuf[i] = nil
+    	end
+end
+
+mt = { __concat = concatbuf, __tostring = function(s) return dump(s, '\n') end ,  __eq=eqbuf}
+
+new = function(val)
+	local tmp ={}
+	setmetatable(tmp, mt)
+	if val ~=nil then
+		table.insert(tmp, val)
+	end
+	return tmp
+end
+
+
+