diff --git a/contrib/gana b/contrib/gana
index 560c1ac1d..b0dd85e81 160000
--- a/contrib/gana
+++ b/contrib/gana
@@ -1 +1 @@
-Subproject commit 560c1ac1d321f7da4fc43ef96858ac27b7eaa2bd
+Subproject commit b0dd85e8187f33a1f92dd5eb31082050d333e168
diff --git a/src/exchangedb/exchangedb_plugin.c b/src/exchangedb/exchangedb_plugin.c
index 21bb032f3..5dc41d988 100644
--- a/src/exchangedb/exchangedb_plugin.c
+++ b/src/exchangedb/exchangedb_plugin.c
@@ -24,12 +24,6 @@
 #include <ltdl.h>
 
 
-/**
- * Initialize the plugin.
- *
- * @param cfg configuration to use
- * @return #GNUNET_OK on success
- */
 struct TALER_EXCHANGEDB_Plugin *
 TALER_EXCHANGEDB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
@@ -62,11 +56,6 @@ TALER_EXCHANGEDB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
 }
 
 
-/**
- * Shutdown the plugin.
- *
- * @param plugin the plugin to unload
- */
 void
 TALER_EXCHANGEDB_plugin_unload (struct TALER_EXCHANGEDB_Plugin *plugin)
 {
diff --git a/src/include/taler_json_lib.h b/src/include/taler_json_lib.h
index 3d6f6a7c8..102b3a6ff 100644
--- a/src/include/taler_json_lib.h
+++ b/src/include/taler_json_lib.h
@@ -557,7 +557,7 @@ TALER_extension_config_hash (const json_t *config,
  *
  * @param root is the json object
  * @param[out] mask on succes, will contain the age mask
- * @return GNUNET_OK on success and GNUNET_SYSERR on failure.
+ * @return #GNUNET_OK on success and #GNUNET_SYSERR on failure.
  */
 enum GNUNET_GenericReturnValue
 TALER_agemask_parse_json (const json_t *root,
diff --git a/src/include/taler_mhd_lib.h b/src/include/taler_mhd_lib.h
index 7f38ffcf5..b0012a645 100644
--- a/src/include/taler_mhd_lib.h
+++ b/src/include/taler_mhd_lib.h
@@ -249,6 +249,17 @@ TALER_MHD_make_json_pack (const char *fmt,
   TALER_MHD_make_json_steal (GNUNET_JSON_PACK (__VA_ARGS__))
 
 
+/**
+ * Pack Taler error code @a ec and associated hint into a
+ * JSON object.
+ *
+ * @param ec error code to pack
+ * @return packer array entries (two!)
+ */
+#define TALER_MHD_PACK_EC(ec) \
+  GNUNET_JSON_pack_uint64 ("code", ec), \
+  GNUNET_JSON_pack_string ("hint", TALER_ErrorCode_get_hint (ec))
+
 /**
  * Create a response indicating an internal error.
  *
diff --git a/src/mhd/mhd_responses.c b/src/mhd/mhd_responses.c
index 2918440a2..a639f4052 100644
--- a/src/mhd/mhd_responses.c
+++ b/src/mhd/mhd_responses.c
@@ -371,8 +371,7 @@ TALER_MHD_make_error (enum TALER_ErrorCode ec,
                       const char *detail)
 {
   return TALER_MHD_MAKE_JSON_PACK (
-    GNUNET_JSON_pack_uint64 ("code", ec),
-    GNUNET_JSON_pack_string ("hint", TALER_ErrorCode_get_hint (ec)),
+    TALER_MHD_PACK_EC (ec),
     GNUNET_JSON_pack_allow_null (
       GNUNET_JSON_pack_string ("detail", detail)));
 }
@@ -387,8 +386,7 @@ TALER_MHD_reply_with_error (struct MHD_Connection *connection,
   return TALER_MHD_REPLY_JSON_PACK (
     connection,
     http_status,
-    GNUNET_JSON_pack_uint64 ("code", ec),
-    GNUNET_JSON_pack_string ("hint", TALER_ErrorCode_get_hint (ec)),
+    TALER_MHD_PACK_EC (ec),
     GNUNET_JSON_pack_allow_null (
       GNUNET_JSON_pack_string ("detail", detail)));
 }