--- a/plugins/presence.js
+++ b/plugins/presence.js
@@ -24,32 +24,34 @@
   var legal_types = ['error', 'probe', 'subscribe', 'subscribed', 'unavailable', 'unsubscribe', 'unsubscribed'];
 
   Lightstring.stanza.presence = function(object) {
-    var aPriority, aShow, aStatus;
-    var payloads = "";
-    var attributs = "";
+    if (object) {
+      var payloads = "";
+      var attributs = "";
+      if (object.type && legal_types.indexOf(object.type) !== -1)
+        attributs += " type='" + object.type + "'";
 
-    if (object.type && legal_types.indexOf(object.type) !== -1)
-      attributs += " type='" + object.type + "'";
+      if (object.priority)
+        payloads += "<priority>" + object.priority + "</priority>";
 
-    if (object.priority)
-      payloads += "<priority>" + object.priority + "</priority>";
+      if (object.show)
+        payloads += "<show>" + object.show + "</show>";
 
-    if (object.show)
-      payloads += "<show>" + object.show + "</show>";
+      if (object.status)
+        payloads += "<status>" + object.status + "</status>";
 
-    if (object.status)
-      payloads += "<status>" + object.status + "</status>";
+      if (object.payload)
+        payloads += object.payload;
 
-    if (object.payload)
-      payloads += object.payload;
+      if (payloads)
+        return "<presence" + attributs + ">" + payloads + "</presence>";
+      else
+        return "<presence" + attributs + "/>";
 
-    if (payloads)
-      return "<presence" + attributs + ">" + payloads + "</presence>";
-    else
-      return "<presence" + attributs + "/>";
+    } else
+      return "<presence/>";
   };
 
-  Lightstring.presence = function(aConnection, aPriority) {
-    aConnection.send(Lightstring.stanza.presence(aPriority));
+  Lightstring.presence = function(aConnection, aObject) {
+    aConnection.send(Lightstring.stanza.presence(aObject));
   };
 })();