--- state_flow.module	2013-09-06 11:26:35.488283697 +0200
+++ state_flow.module.fixed	2013-09-06 11:26:10.944099205 +0200
@@ -196,7 +196,10 @@
 /**
  * Implements hook_node_update().
  */
-function state_flow_node_update($node) {
+function state_flow_entity_update($node, $type = 'node') {
+  if ($type != 'node') {
+    return;
+  }
   global $user;
   $state_flow = state_flow_load_state_machine($node);
   $options = $state_flow->get_states_options();