diff --git a/frappy/modulebase.py b/frappy/modulebase.py
index 9d25648a..de3bb704 100644
--- a/frappy/modulebase.py
+++ b/frappy/modulebase.py
@@ -348,7 +348,7 @@ class Module(HasAccessibles):
         self.attachedModules = {}
         self.errors = []
         self._isinitialized = False
-        self.updateCallback =  srv.dispatcher.announce_update
+        self.updateCallback = srv.dispatcher.announce_update
 
         # handle module properties
         # 1) make local copies of properties
@@ -549,7 +549,7 @@ class Module(HasAccessibles):
                 arg = value
                 pobj.readerror = None
             if pobj.export:
-                self.updateCallback(self.name, pname, pobj)
+                self.updateCallback(self, pobj)
             cblist = callbacks[pname]
             for cb in cblist:
                 try:
diff --git a/frappy/modules.py b/frappy/modules.py
index 39dc7066..62026384 100644
--- a/frappy/modules.py
+++ b/frappy/modules.py
@@ -133,6 +133,9 @@ class Attached(Property):
             if not modulename:
                 return None  # happens when mandatory=False and modulename is not given
             modobj = obj.secNode.get_module(modulename)
+            if not modobj:
+                raise ConfigError(f'attached module {self.name}={modulename!r} '
+                                  f'does not exist')
             if not isinstance(modobj, self.basecls):
                 raise ConfigError(f'attached module {self.name}={modobj.name!r} '
                                   f'must inherit from {self.basecls.__qualname__!r}')
diff --git a/frappy/playground.py b/frappy/playground.py
index 0b7f88eb..7b2deeb8 100644
--- a/frappy/playground.py
+++ b/frappy/playground.py
@@ -81,14 +81,14 @@ class Dispatcher(dispatcher.Dispatcher):
         super().__init__(name, log, options, srv)
         self.log = srv.log  # overwrite child logger
 
-    def announce_update(self, modulename, pname, pobj):
+    def announce_update(self, moduleobj, pobj):
         if pobj.readerror:
             value = repr(pobj.readerror)
         else:
             value = pobj.value
-        logobj = self._modules.get(modulename, self)
+        logobj = self._modules.get(moduleobj.name, self)
         # self.log.info('%s:%s %r', modulename, pname, value)
-        logobj.log.info('%s %r', pname, value)
+        logobj.log.info('%s %r', pobj.name, value)
 
     def register_module(self, moduleobj, modulename, export=True):
         self.log.info('registering %s', modulename)
diff --git a/frappy/protocol/dispatcher.py b/frappy/protocol/dispatcher.py
index aa60956e..cc95e23d 100644
--- a/frappy/protocol/dispatcher.py
+++ b/frappy/protocol/dispatcher.py
@@ -93,10 +93,10 @@ class Dispatcher:
         for conn in listeners:
             conn.send_reply(msg)
 
-    def announce_update(self, modulename, pname, pobj):
+    def announce_update(self, moduleobj, pobj):
         """called by modules param setters to notify subscribers of new values
         """
-        self.broadcast_event(make_update(modulename, pobj))
+        self.broadcast_event(make_update(moduleobj.name, pobj))
 
     def subscribe(self, conn, eventname):
         self._subscriptions.setdefault(eventname, set()).add(conn)
diff --git a/frappy/secnode.py b/frappy/secnode.py
index 6b7b91a3..b2ea18e0 100644
--- a/frappy/secnode.py
+++ b/frappy/secnode.py
@@ -94,6 +94,7 @@ class SecNode:
         if modulename in list(self.modules.values()):
             # it's actually already the module object
             return modulename
+
         # create module from srv.module_cfg, store and return
         self.log.debug('attempting to create module %r', modulename)
 
diff --git a/test/test_attach.py b/test/test_attach.py
index b57f05a0..551fedad 100644
--- a/test/test_attach.py
+++ b/test/test_attach.py
@@ -23,29 +23,6 @@ from frappy.modules import Module, Attached
 from frappy.protocol.dispatcher import Dispatcher
 
 
-# class DispatcherStub:
-#     # omit_unchanged_within = 0
-#
-#     # def __init__(self, updates):
-#     #     self.updates = updates
-#     #
-#     # def announce_update(self, modulename, pname, pobj):
-#     #     self.updates.setdefault(modulename, {})
-#     #     if pobj.readerror:
-#     #         self.updates[modulename]['error', pname] = str(pobj.readerror)
-#     #     else:
-#     #         self.updates[modulename][pname] = pobj.value
-#
-#     def __init__(self):
-#         self.modules = {}
-#
-#     def get_module(self, name):
-#         return self.modules[name]
-#
-#     def register_module(self, name, module):
-#         self.modules[name] = module
-
-
 class LoggerStub:
     def debug(self, fmt, *args):
         print(fmt % args)
diff --git a/test/test_handler.py b/test/test_handler.py
index 26d87ba0..0fb5e5e3 100644
--- a/test/test_handler.py
+++ b/test/test_handler.py
@@ -36,12 +36,13 @@ class DispatcherStub:
         generalConfig.testinit(omit_unchanged_within=0)
         self.updates = updates
 
-    def announce_update(self, modulename, pname, pobj):
+    def announce_update(self, moduleobj, pobj):
+        modulename = moduleobj.name
         self.updates.setdefault(modulename, {})
         if pobj.readerror:
-            self.updates[modulename]['error', pname] = str(pobj.readerror)
+            self.updates[modulename]['error', pobj.name] = str(pobj.readerror)
         else:
-            self.updates[modulename][pname] = pobj.value
+            self.updates[modulename][pobj.name] = pobj.value
 
 
 class LoggerStub:
diff --git a/test/test_modules.py b/test/test_modules.py
index e18a107e..5a1f4984 100644
--- a/test/test_modules.py
+++ b/test/test_modules.py
@@ -43,12 +43,13 @@ class DispatcherStub:
         generalConfig.testinit(omit_unchanged_within=0)
         self.updates = updates
 
-    def announce_update(self, modulename, pname, pobj):
+    def announce_update(self, moduleobj, pobj):
+        modulename = moduleobj.name
         self.updates.setdefault(modulename, {})
         if pobj.readerror:
-            self.updates[modulename]['error', pname] = str(pobj.readerror)
+            self.updates[modulename]['error', pobj.name] = str(pobj.readerror)
         else:
-            self.updates[modulename][pname] = pobj.value
+            self.updates[modulename][pobj.name] = pobj.value
 
 
 class LoggerStub:
@@ -706,10 +707,10 @@ def test_super_call():
         def __init__(self, updates):
             self.updates = updates
 
-        def announce_update(self, modulename, pname, pobj):
+        def announce_update(self, moduleobj, pobj):
             if pobj.readerror:
                 raise pobj.readerror
-            self.updates.append((modulename, pname, pobj.value))
+            self.updates.append((moduleobj.name, pobj.name, pobj.value))
 
     class ServerStub1:
         def __init__(self, updates):
diff --git a/test/test_persistent.py b/test/test_persistent.py
index be931cd6..1dd74fc4 100644
--- a/test/test_persistent.py
+++ b/test/test_persistent.py
@@ -34,7 +34,7 @@ class SecNodeStub:
 
 
 class DispatcherStub:
-    def announce_update(self, modulename, pname, pobj):
+    def announce_update(self, moduleobj, pobj):
         pass
 
 
diff --git a/test/test_poller.py b/test/test_poller.py
index 1a2f85f9..077c40c9 100644
--- a/test/test_poller.py
+++ b/test/test_poller.py
@@ -52,7 +52,7 @@ artime = Time()  # artificial test time
 class DispatcherStub:
     maxcycles = 10
 
-    def announce_update(self, modulename, pname, pobj):
+    def announce_update(self, moduleobj, pobj):
         now = artime.time()
         if hasattr(pobj, 'stat'):
             pobj.stat.append(now)
diff --git a/test/test_statemachine.py b/test/test_statemachine.py
index 876480c7..a91371ad 100644
--- a/test/test_statemachine.py
+++ b/test/test_statemachine.py
@@ -194,12 +194,12 @@ class DispatcherStub:
         generalConfig.testinit(omit_unchanged_within=0)
         self.updates = updates
 
-    def announce_update(self, modulename, pname, pobj):
-        assert modulename == 'obj'
+    def announce_update(self, moduleobj, pobj):
+        assert moduleobj.name == 'obj'
         if pobj.readerror:
-            self.updates.append((pname, pobj.readerror))
+            self.updates.append((pobj.name, pobj.readerror))
         else:
-            self.updates.append((pname, pobj.value))
+            self.updates.append((pobj.name, pobj.value))
 
 
 class ServerStub: