diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..447d533
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+*~
+kamailio
diff --git a/kam_utils.lua b/kam_utils.lua
new file mode 100644
index 0000000..4c229cd
--- /dev/null
+++ b/kam_utils.lua
@@ -0,0 +1,34 @@
+#!/usr/bin/env lua5.1
+# Kamailio Lua utils
+
+-- cleans and sets string values from the table list
+function sets_avps(list)
+    local i, v
+
+    for i,v in pairs(list) do
+        -- sr.log("debug","i:" .. i .. " v:" .. v)
+        sr.pv.unset('$avp(' .. i ..')[*]')
+        sr.pv.sets('$avp(' .. i .. ')', v)
+    end
+end
+
+-- cleans and sets int values from the table list
+function seti_avps(list)
+    local i, v
+
+    for i,v in pairs(list) do
+        -- sr.log("debug","i:" .. i .. " v:" .. v)
+        sr.pv.unset('$avp(' .. i ..')[*]')
+        sr.pv.seti('$avp(' .. i .. ')', v)
+    end
+end
+
+function clean_avps(list)
+    local i,v
+
+    for i,v in pairs(list) do
+        sr.pv.unset('$avp(' .. i .. ')[*]')
+    end
+end
+
+#EOF
\ No newline at end of file
diff --git a/kamalio_conf.lua b/kamalio_conf.lua
new file mode 100644
index 0000000..1c84fdd
--- /dev/null
+++ b/kamalio_conf.lua
@@ -0,0 +1,36 @@
+#!/usr/bin/env lua5.1
+-- Kamailio Lua Config
+require "kam_utils.lua"
+
+-- ROUTE_CLEAR_PEER_IN_PREF
+function clear_peer_in_pref()
+    local list = {
+        peer_peer_callee_auth_user,
+        peer_peer_callee_auth_pass,
+        peer_peer_callee_auth_realm,
+        caller_use_rtpproxy,
+        peer_caller_ipv46_for_rtpproxy,
+        caller_force_outbound_calls_to_peer,
+        peer_caller_find_subscriber_by_uuid,
+        pstn_dp_caller_in_id,
+        pstn_dp_callee_in_id,
+        pstn_dp_caller_out_id,
+        pstn_dp_callee_out_id,
+        rewrite_caller_in_dpid,
+        rewrite_caller_out_dpid,
+        rewrite_callee_in_dpid,
+        rewrite_callee_out_dpid,
+        caller_peer_concurrent_max,
+        peer_caller_sst_enable,
+        peer_caller_sst_expires,
+        peer_caller_sst_min_timer,
+        peer_caller_sst_max_timer,
+        peer_caller_sst_refresh_method,
+        caller_inbound_upn,
+        caller_inbound_npn,
+        caller_inbound_uprn
+    }
+
+    clean_avps(list)
+end
+
diff --git a/utils.lua b/utils.lua
new file mode 100644
index 0000000..d6ec83e
--- /dev/null
+++ b/utils.lua
@@ -0,0 +1,101 @@
+#!/usr/bin/env lua5.1
+# Lua utils
+
+-- kamailio log for a table
+function log_table(table, msg, level)
+    if not level then
+        level = "debug"
+    end
+    if msg then
+        sr.log(level, msg)
+    end
+    if not table then
+        -- empty table
+        return
+    end
+    for i,v in pairs(table) do
+        if type(i) == "number" then
+            iformat = "%d"
+        elseif type(i) == "string" then
+            iformat = "%s"
+        end
+        if type(v) == "string" then
+            sr.log(level, string.format("i:" .. iformat .. " v: %s", i, v))
+        elseif type(v) == "number" then
+            sr.log(level, string.format("i:" .. iformat .. " v: %d", i, v))
+        elseif type(v) == "table" then
+            log_table(v,string.format("i:" .. iformat .. " v:", i),level)
+        end
+    end
+end
+
+-- copy a table
+function table_deepcopy(object)
+    local lookup_table = {}
+    local function _copy(object)
+        if type(object) ~= "table" then
+            return object
+        elseif lookup_table[object] then
+            return lookup_table[object]
+        end
+        local new_table = {}
+        lookup_table[object] = new_table
+        for index, value in pairs(object) do
+            new_table[_copy(index)] = _copy(value)
+        end
+        return setmetatable(new_table, getmetatable(object))
+    end
+    return _copy(object)
+end
+
+-- from table to string
+-- t = {'a','b'}
+-- implode(",",t,"'")
+-- "'a','b'"
+-- implode("#",t)
+-- "a#b"
+function implode(delimiter, list, quoter)
+    local len = #list
+    if len == 0 then
+            return nil
+        end
+        if not quoter then
+            quoter = ""
+        end
+        local string = quoter .. list[1] .. quoter
+        for i = 2, len do
+            string = string .. delimiter .. quoter .. list[i] .. quoter
+        end
+        return string
+end
+
+-- from string to table
+function explode(delimiter, text)
+  local list = {}; local pos = 1
+  if string.find("", delimiter, 1) then
+    -- We'll look at error handling later!
+    error("delimiter matches empty string!")
+  end
+  while 1 do
+    local first, last = string.find(text, delimiter, pos)
+    print (first, last)
+    if first then
+      table.insert(list, string.sub(text, pos, first-1))
+      pos = last+1
+    else
+      table.insert(list, string.sub(text, pos))
+      break
+    end
+  end
+  return list
+end
+
+function compare_desc_len(a,b)
+    return string.len(a) > string.len(b)
+end
+
+function findpattern(text, pattern, start)
+    return string.sub(text, string.find(text, pattern, start))
+end
+
+#EOF
\ No newline at end of file