diff --git a/app/operations/gimpoperationcagetransform.c b/app/operations/gimpoperationcagetransform.c
index 61c4f3fc97e..be221226595 100644
--- a/app/operations/gimpoperationcagetransform.c
+++ b/app/operations/gimpoperationcagetransform.c
@@ -111,7 +111,8 @@ gimp_operation_cage_transform_class_init (GimpOperationCageTransformClass *klass
                   0,
                   NULL, NULL,
                   gimp_marshal_VOID__DOUBLE,
-                  G_TYPE_NONE, 0);
+                  G_TYPE_NONE, 1,
+                  G_TYPE_DOUBLE);
 
   object_class->get_property               = gimp_operation_cage_transform_get_property;
   object_class->set_property               = gimp_operation_cage_transform_set_property;
diff --git a/app/operations/gimpoperationshapeburst.c b/app/operations/gimpoperationshapeburst.c
index bcf8d450f60..26a414f3d0d 100644
--- a/app/operations/gimpoperationshapeburst.c
+++ b/app/operations/gimpoperationshapeburst.c
@@ -92,7 +92,8 @@ gimp_operation_shapeburst_class_init (GimpOperationShapeburstClass *klass)
                   0,
                   NULL, NULL,
                   gimp_marshal_VOID__DOUBLE,
-                  G_TYPE_NONE, 0);
+                  G_TYPE_NONE, 1,
+                  G_TYPE_DOUBLE);
 
   object_class->set_property   = gimp_operation_shapeburst_set_property;
   object_class->get_property   = gimp_operation_shapeburst_get_property;