diff --git a/tryton/common/common.py b/tryton/common/common.py
index 8ca80e3219..b130f96e93 100644
--- a/tryton/common/common.py
+++ b/tryton/common/common.py
@@ -187,12 +187,12 @@ class ViewSearch(object):
     def add(self, model, name, domain):
         domain = PYSONEncoder().encode(domain)
         try:
-            id_ = RPCExecute('model', 'ir.ui.view_search',
-                'create', {
-                    'model': model,
-                    'name': name,
-                    'domain': domain,
-                    })
+            id_, = RPCExecute('model', 'ir.ui.view_search',
+                'create', [{
+                        'model': model,
+                        'name': name,
+                        'domain': domain,
+                        }])
         except RPCException:
             return
         self.searches.setdefault(model, []).append((id_, name, domain))
@@ -1049,11 +1049,11 @@ def process_exception(exception, *args, **kwargs):
             name, msg, description = exception.args
             res = userwarning(description, msg)
             if res in ('always', 'ok'):
-                args2 = ('model', 'res.user.warning', 'create', {
-                        'user': rpc._USER,
-                        'name': name,
-                        'always': (res == 'always'),
-                        }, rpc.CONTEXT)
+                args2, = ('model', 'res.user.warning', 'create', [{
+                            'user': rpc._USER,
+                            'name': name,
+                            'always': (res == 'always'),
+                            }], rpc.CONTEXT)
                 try:
                     rpc_execute(*args2)
                 except TrytonServerError, exception:
diff --git a/tryton/gui/window/view_form/model/field.py b/tryton/gui/window/view_form/model/field.py
index 57cd682792..eb7c223cd5 100644
--- a/tryton/gui/window/view_form/model/field.py
+++ b/tryton/gui/window/view_form/model/field.py
@@ -530,6 +530,7 @@ class O2MField(CharField):
         record_deleted = record.value[self.name].record_deleted
         result = [('add', [])]
         parent_name = self.attrs.get('relation_field', '')
+        to_create = []
         for record2 in record.value[self.name]:
             if record2 in record_removed or record2 in record_deleted:
                 continue
@@ -542,7 +543,9 @@ class O2MField(CharField):
             else:
                 values = record2.get()
                 values.pop(parent_name, None)
-                result.append(('create', values))
+                to_create.append(values)
+        if to_create:
+            result.append(('create', to_create))
         if not result[0][1]:
             del result[0]
         if record_removed:
diff --git a/tryton/gui/window/view_form/model/record.py b/tryton/gui/window/view_form/model/record.py
index ddd85939ae..591bec59df 100644
--- a/tryton/gui/window/view_form/model/record.py
+++ b/tryton/gui/window/view_form/model/record.py
@@ -267,8 +267,8 @@ class Record(SignalEvent):
             if self.id < 0:
                 value = self.get()
                 try:
-                    res = RPCExecute('model', self.model_name, 'create', value,
-                        context=self.context_get())
+                    res, = RPCExecute('model', self.model_name, 'create',
+                        [value], context=self.context_get())
                 except RPCException:
                     return False
                 old_id = self.id
diff --git a/tryton/gui/window/win_export.py b/tryton/gui/window/win_export.py
index 1fc34e16c2..ef582708ff 100644
--- a/tryton/gui/window/win_export.py
+++ b/tryton/gui/window/win_export.py
@@ -313,13 +313,13 @@ class WinExport(NoModal):
             fields.append(field_name)
             iter = self.model2.iter_next(iter)
         try:
-            new_id = RPCExecute('model', 'ir.export', 'create', {
+            new_id, = RPCExecute('model', 'ir.export', 'create', [{
                     'name': name,
                     'resource': self.model,
-                    'export_fields': [('create', {
+                    'export_fields': ('create', [{
                                 'name': x,
-                                }) for x in fields],
-                    })
+                                } for x in fields]),
+                    }])
         except RPCException:
             return
         self.predef_model.append((