diff --git a/pyipmi/interfaces/aardvark.py b/pyipmi/interfaces/aardvark.py
index 26c9a3f1..f68895c0 100644
--- a/pyipmi/interfaces/aardvark.py
+++ b/pyipmi/interfaces/aardvark.py
@@ -199,7 +199,7 @@ def send_and_receive(self, req):
                                          netfn=req.netfn,
                                          cmdid=req.cmdid,
                                          payload=encode_message(req))
-        rsp = create_message(req.cmdid, req.netfn + 1)
+        rsp = create_message(req.netfn + 1, req.cmdid)
         decode_message(rsp, rx_data)
 
         log().debug('IPMI Response [%s])', rsp)
diff --git a/pyipmi/interfaces/ipmb.py b/pyipmi/interfaces/ipmb.py
index 5cac6215..2df8b02d 100644
--- a/pyipmi/interfaces/ipmb.py
+++ b/pyipmi/interfaces/ipmb.py
@@ -167,8 +167,8 @@ def decode_bridged_message(rx_data):
     """
 
     while array('B', rx_data)[5] == constants.CMDID_SEND_MESSAGE:
-        rsp = create_message(constants.CMDID_SEND_MESSAGE,
-                             constants.NETFN_APP+1)
+        rsp = create_message(constants.NETFN_APP + 1,
+                             constants.CMDID_SEND_MESSAGE)
         decode_message(rsp, rx_data[6:])
         check_completion_code(rsp.completion_code)
         rx_data = rx_data[7:-1]
diff --git a/pyipmi/interfaces/ipmitool.py b/pyipmi/interfaces/ipmitool.py
index 01c420b0..4556cede 100644
--- a/pyipmi/interfaces/ipmitool.py
+++ b/pyipmi/interfaces/ipmitool.py
@@ -144,7 +144,7 @@ def send_and_receive(self, req):
         rsp_data = self.send_and_receive_raw(req.target, req.lun, req.netfn,
                                              req_data.tostring())
 
-        rsp = create_message(req.cmdid, req.netfn + 1)
+        rsp = create_message(req.netfn + 1, req.cmdid)
         decode_message(rsp, rsp_data)
         log().debug('IPMI Response [%s])', rsp)
 
diff --git a/pyipmi/interfaces/rmcp.py b/pyipmi/interfaces/rmcp.py
index d4c4cfa7..8e772efa 100644
--- a/pyipmi/interfaces/rmcp.py
+++ b/pyipmi/interfaces/rmcp.py
@@ -567,6 +567,6 @@ def send_and_receive(self, req):
                                          netfn=req.netfn,
                                          cmdid=req.cmdid,
                                          payload=encode_message(req))
-        rsp = create_message(req.cmdid, req.netfn + 1)
+        rsp = create_message(req.netfn + 1, req.cmdid)
         decode_message(rsp, rx_data)
         return rsp
diff --git a/pyipmi/msgs/registry.py b/pyipmi/msgs/registry.py
index 98b51f2a..dbc2c4f6 100644
--- a/pyipmi/msgs/registry.py
+++ b/pyipmi/msgs/registry.py
@@ -29,7 +29,7 @@ def register_class(self, cls):
         if cls.__name__[-3:] not in ('Req', 'Rsp'):
             raise DescriptionError('Class name has to end in Req or Rsp')
         # (2) mandantory fields
-        for attr in ('__cmdid__', '__netfn__', '__default_lun__'):
+        for attr in ('__netfn__', '__cmdid__', '__default_lun__'):
             if not hasattr(cls, attr):
                 raise DescriptionError('Class has to have attribute "%s"' %
                                        attr)
@@ -44,7 +44,7 @@ def register_class(self, cls):
         if cls.__name__ in self.registry:
             raise DescriptionError('Message %s already registered' %
                                    cls.__name__)
-        msg_id = (cls.__cmdid__, cls.__netfn__)
+        msg_id = (cls.__netfn__, cls.__cmdid__)
         if msg_id in self.registry:
             raise DescriptionError('Message (%d,%d) already registered (%s)'
                                    % (msg_id[0], msg_id[1],
@@ -53,7 +53,7 @@ def register_class(self, cls):
         # register name
         self.registry[cls.__name__] = cls
         # register (netfn, cmdid) tuple
-        self.registry[(cls.__cmdid__, cls.__netfn__)] = cls
+        self.registry[(cls.__netfn__, cls.__cmdid__)] = cls
 
         # register
         return cls