Index: usernode.
===================================================================
--- usernode.module	(revision 172)
+++ usernode.module	(working copy)
@@ -271,8 +271,12 @@
   $node = usernode_get_node($user);
   //make sure the node is associated with the updated $user and save it again,
   //so the usernode is updated
-  $node->user = $user;
-  usernode_save_node($node);
+  if($node) {
+    $node->user = $user;
+    usernode_save_node($node);
+  } else {
+    usernode_create_node($user);
+  }
 }
 
 /**