fix translation for older versions of engine

* the intlib is working but not as proposed
* if there no translation provided do a mock for translations
* this made compatiblity for any version of the engine

api.lua

@@ -1,7 +1,39 @@
 -- Load support for intllib.
 local MP = minetest.get_modpath(minetest.get_current_modname())
-local S = minetest.get_translator and minetest.get_translator("mobs") or
-		dofile(MP .. "/intllib.lua")
+local S
+
+if minetest.get_translator ~= nil then
+	S = minetest.get_translator("mobs")
+else
+	if minetest.get_modpath("intllib") then
+		dofile(minetest.get_modpath("intllib").."/init.lua")
+		if intllib.make_gettext_pair then
+			-- New method using gettext.
+			gettext, ngettext = intllib.make_gettext_pair()
+		else
+			-- Old method using text files.
+			gettext = intllib.Getter()
+		end
+		S = gettext
+	else
+		-- mock the translator function for MT 0.4
+		function minetest.translate(textdomain, str, ...)
+			local arg = {n=select('#', ...), ...}
+			return str:gsub("@(.)", function(matched)
+				local c = string.byte(matched)
+				if string.byte("1") <= c and c <= string.byte("9") then
+					return arg[c - string.byte("0")]
+				else
+					return matched
+				end
+			end)
+		end
+		function minetest.get_translator(textdomain)
+			return function(str, ...) return  minetest.translate(textdomain or "", str, ...) end
+		end
+		S = minetest.get_translator("mobs")
+	end
+end
 
 -- CMI support check
 local use_cmi = minetest.global_exists("cmi")