diff --git a/src/plugins/plugin.c b/src/plugins/plugin.c
index 2e05024eb..5c1ed5ee1 100644
--- a/src/plugins/plugin.c
+++ b/src/plugins/plugin.c
@@ -402,6 +402,7 @@ plugin_load (const char *filename)
         new_plugin->config_option_rename = &config_file_option_rename;
         new_plugin->config_option_get_pointer = &config_file_option_get_pointer;
         new_plugin->config_option_is_null = &config_file_option_is_null;
+        new_plugin->config_option_default_is_null = &config_file_option_default_is_null;
         new_plugin->config_boolean = &config_file_option_boolean;
         new_plugin->config_boolean_default = &config_file_option_boolean_default;
         new_plugin->config_integer = &config_file_option_integer;