diff --git a/lib/masterd/instance.py b/lib/masterd/instance.py
index 5ede2746704420fe698d701154d3237f2fa7fd19..8211f3188023c8eec0e2bddadb91cc38962961e2 100644
--- a/lib/masterd/instance.py
+++ b/lib/masterd/instance.py
@@ -530,7 +530,7 @@ class DiskImport(_DiskImportExportBase):
     """
     return self._lu.rpc.call_import_start(self.node_name, self._opts,
                                           self._instance, self._component,
-                                          self._dest, self._dest_args)
+                                          (self._dest, self._dest_args))
 
   def CheckListening(self):
     """Checks whether the daemon is listening.
@@ -616,7 +616,7 @@ class DiskExport(_DiskImportExportBase):
     return self._lu.rpc.call_export_start(self.node_name, self._opts,
                                           self._dest_host, self._dest_port,
                                           self._instance, self._component,
-                                          self._source, self._source_args)
+                                          (self._source, self._source_args))
 
   def CheckListening(self):
     """Checks whether the daemon is listening.
diff --git a/lib/rpc.py b/lib/rpc.py
index fcead58f94baa8ebe8775916ca60530eeebefb56..c73e701245693ea88b88a662fccc1dd12cf667b8 100644
--- a/lib/rpc.py
+++ b/lib/rpc.py
@@ -565,19 +565,19 @@ class RpcRunner(_generated_rpc.RpcClientDefault,
     return result
 
   @staticmethod
-  def _EncodeImportExportIO(ieio, ieioargs):
+  def _EncodeImportExportIO((ieio, ieioargs)):
     """Encodes import/export I/O information.
 
     """
     if ieio == constants.IEIO_RAW_DISK:
       assert len(ieioargs) == 1
-      return (ieioargs[0].ToDict(), )
+      return (ieio, (ieioargs[0].ToDict(), ))
 
     if ieio == constants.IEIO_SCRIPT:
       assert len(ieioargs) == 2
-      return (ieioargs[0].ToDict(), ieioargs[1])
+      return (ieio, (ieioargs[0].ToDict(), ieioargs[1]))
 
-    return ieioargs
+    return (ieio, ieioargs)
 
   @staticmethod
   def _PrepareFileUpload(filename):
diff --git a/lib/rpc_defs.py b/lib/rpc_defs.py
index 1e22549573507ff30932100345314c57128254d1..a3ba76f17d606a2fb52f873d1eaf13a50fdbb53d 100644
--- a/lib/rpc_defs.py
+++ b/lib/rpc_defs.py
@@ -165,8 +165,7 @@ _IMPEXP_CALLS = [
     ("opts", OBJECT_TO_DICT, None),
     ("instance", INST_TO_DICT, None),
     ("component", None, None),
-    ("dest", None, None),
-    ("dest_args", "self._EncodeImportExportIO(dest, %s)", None),
+    ("dest", "self._EncodeImportExportIO(%s)", "Import destination"),
     ], None, "Starts an import daemon"),
   ("export_start", SINGLE, TMO_NORMAL, [
     ("opts", OBJECT_TO_DICT, None),
@@ -174,8 +173,7 @@ _IMPEXP_CALLS = [
     ("port", None, None),
     ("instance", INST_TO_DICT, None),
     ("component", None, None),
-    ("source", None, None),
-    ("source_args", "self._EncodeImportExportIO(source, %s)", None),
+    ("source", "self._EncodeImportExportIO(%s)", "Export source"),
     ], None, "Starts an export daemon"),
   ("impexp_status", SINGLE, TMO_FAST, [
     ("names", None, "Import/export names"),
diff --git a/lib/server/noded.py b/lib/server/noded.py
index 90d879f9ea5ce92e7b32c7c15fb410abc745db0e..2f951c72b4ce3410228c01d9e1241ff58a9aeafc 100644
--- a/lib/server/noded.py
+++ b/lib/server/noded.py
@@ -951,7 +951,7 @@ class NodeHttpServer(http.server.HttpServer):
     """Starts an import daemon.
 
     """
-    (opts_s, instance, component, dest, dest_args) = params
+    (opts_s, instance, component, (dest, dest_args)) = params
 
     opts = objects.ImportExportOptions.FromDict(opts_s)
 
@@ -967,7 +967,7 @@ class NodeHttpServer(http.server.HttpServer):
     """Starts an export daemon.
 
     """
-    (opts_s, host, port, instance, component, source, source_args) = params
+    (opts_s, host, port, instance, component, (source, source_args)) = params
 
     opts = objects.ImportExportOptions.FromDict(opts_s)