diff --git a/scripts/telegram.coffee b/scripts/telegram.coffee
index eaa995a..83abc03 100644
--- a/scripts/telegram.coffee
+++ b/scripts/telegram.coffee
@@ -111,11 +111,18 @@ module.exports = (robot) ->
         res.send res.random denied
         return
       res.send res.random ok
-    
-      run_command "chat_add_user #{chat} #{user}", (reply) ->
+      
+      norm = (x) -> x.replace /\ /g, '_'
+
+      run_command "chat_add_user #{norm chat} #{norm user}", (reply) ->
         robot.logger.info "add user #{user} to chat #{chat}"
-        robot.logger.info 'result: ' + reply
-        if (reply.split ' ')[-1..][0] is 'USER_NOT_MUTUAL_CONTACT'
-          res.send 'aah, non posso: ho bisogno del tuo contatto'
-        else
+        robot.logger.info 'result: ' + reply[0]
+        err = (reply[0].split ' ')[-1..][0]
+        if err is 'SUCCESS'
           res.send res.random done
+        else if err is 'USER_NOT_MUTUAL_CONTACT'
+          res.send 'aah, non posso: ho bisogno del tuo contatto'
+        else if err is 'USER_ALREADY_PARTICIPANT'
+          res.send 'ma sei già nel gruppo... [facepalm]'
+        else
+          res.send "non sono riuscito, c'è un errore: #{reply[0]}"