diff --git a/src/include/taler_mintdb_plugin.h b/src/include/taler_mintdb_plugin.h
index 2d1671335..f5e61a7c3 100644
--- a/src/include/taler_mintdb_plugin.h
+++ b/src/include/taler_mintdb_plugin.h
@@ -42,6 +42,13 @@ struct TALER_MINTDB_BankTransfer
    */
   struct TALER_Amount amount;
 
+  /**
+   * When did the mint receive the incoming transaction?
+   * (This is the execution date of the mint's database,
+   * the execution date of the bank should be in @e wire).
+   */
+  struct GNUNET_TIME_Absolute execution_date;
+
   /**
    * Detailed wire information about the transaction.
    */
@@ -724,7 +731,7 @@ struct TALER_MINTDB_Plugin
                          struct TALER_MINTDB_Session *db,
                          const struct TALER_ReservePublicKeyP *reserve_pub,
                          const struct TALER_Amount *balance,
-                         const char *details);
+                         const json_t *details);
 
 
   /**
diff --git a/src/mint-tools/Makefile.am b/src/mint-tools/Makefile.am
index e22df1ed7..9849bbc54 100644
--- a/src/mint-tools/Makefile.am
+++ b/src/mint-tools/Makefile.am
@@ -41,7 +41,7 @@ taler_mint_reservemod_LDADD = \
   $(top_builddir)/src/util/libtalerutil.la \
   $(top_builddir)/src/pq/libtalerpq.la \
   $(top_builddir)/src/mintdb/libtalermintdb.la \
-  -lgnunetutil  $(XLIB)
+  -lgnunetutil -ljansson $(XLIB)
 taler_mint_reservemod_LDFLAGS = \
   $(POSTGRESQL_LDFLAGS)
 taler_mint_reservemod_CPPFLAGS = \
diff --git a/src/mint-tools/taler-mint-reservemod.c b/src/mint-tools/taler-mint-reservemod.c
index 75093fc75..888b34baa 100644
--- a/src/mint-tools/taler-mint-reservemod.c
+++ b/src/mint-tools/taler-mint-reservemod.c
@@ -22,6 +22,7 @@
 #include "platform.h"
 #include <gnunet/gnunet_util_lib.h>
 #include <libpq-fe.h>
+#include <jansson.h>
 #include "taler_mintdb_plugin.h"
 
 /**
@@ -54,6 +55,8 @@ main (int argc, char *const *argv)
   char *add_str = NULL;
   struct TALER_Amount add_value;
   char *details = NULL;
+  json_t *jdetails;
+  json_error_t error;
   struct TALER_ReservePublicKeyP reserve_pub;
   struct TALER_MINTDB_Session *session;
   const struct GNUNET_GETOPT_CommandLineOption options[] = {
@@ -157,11 +160,24 @@ main (int argc, char *const *argv)
              "Failed to initialize DB session\n");
     goto cleanup;
   }
+  jdetails = json_loads (details,
+                         JSON_REJECT_DUPLICATES,
+                         &error);
+  if (NULL == jdetails)
+  {
+    fprintf (stderr,
+             "Failed to parse JSON transaction details `%s': %s (%s)\n",
+             details,
+             error.text,
+             error.source);
+    goto cleanup;
+  }
   ret = plugin->reserves_in_insert (plugin->cls,
 				    session,
 				    &reserve_pub,
 				    &add_value,
-				    details);
+				    jdetails);
+  json_decref (jdetails);
   if (GNUNET_SYSERR == ret)
   {
     fprintf (stderr,
diff --git a/src/mintdb/plugin_mintdb_postgres.c b/src/mintdb/plugin_mintdb_postgres.c
index fe2f2a49c..e4d0f4d50 100644
--- a/src/mintdb/plugin_mintdb_postgres.c
+++ b/src/mintdb/plugin_mintdb_postgres.c
@@ -510,8 +510,8 @@ postgres_prepare (PGconn *db_conn)
            " balance_val"
            ",balance_frac"
            ",balance_curr"
-           ",execution_date" /* NOTE: not used (yet), #3817 */
-           ",details"         /* NOTE: not used (yet), #3817 */
+           ",execution_date"
+           ",details"
            " FROM reserves_in"
            " WHERE reserve_pub=$1",
            1, NULL);
@@ -1150,7 +1150,7 @@ postgres_reserves_in_insert (void *cls,
                              struct TALER_MINTDB_Session *session,
                              const struct TALER_ReservePublicKeyP *reserve_pub,
                              const struct TALER_Amount *balance,
-                             const char *details)
+                             const json_t *details)
 {
   PGresult *result;
   int reserve_exists;
@@ -1212,7 +1212,7 @@ postgres_reserves_in_insert (void *cls,
     struct TALER_PQ_QueryParam params[] = {
       TALER_PQ_query_param_auto_from_type (&reserve.pub),
       TALER_PQ_query_param_amount (balance),
-      TALER_PQ_query_param_fixed_size (details, strlen (details)),
+      TALER_PQ_query_param_json (details),
       TALER_PQ_query_param_absolute_time (&now),
       TALER_PQ_query_param_end
     };
@@ -1490,29 +1490,29 @@ postgres_get_reserve_history (void *cls,
                   "Asked to fetch history for an unknown reserve.\n");
       goto cleanup;
     }
-    /* FIXME: maybe also use the 'expiration_date' and 'details'
-       values and return those as well? While right now they
-       are unnecessary, the 'expiration_date' should become the
-       original transfer date, and then it will be useful;
-       similarly, 'details' might become useful for reserve refunds
-       in the future. (#3817) */
     while (0 < rows)
     {
       bt = GNUNET_new (struct TALER_MINTDB_BankTransfer);
-      /* FIXME: use higher-level libtalerpq API here? */
-      if (GNUNET_OK != TALER_PQ_extract_amount (result,
-                                                --rows,
-                                                "balance_val",
-                                                "balance_frac",
-                                                "balance_curr",
-                                                &bt->amount))
       {
-        GNUNET_free (bt);
-        GNUNET_break (0);
-        goto cleanup;
+        struct TALER_PQ_ResultSpec rs[] = {
+          TALER_PQ_result_spec_amount ("balance",
+                                       &bt->amount),
+          TALER_PQ_result_spec_absolute_time ("execution_date",
+                                              &bt->execution_date),
+          TALER_PQ_result_spec_json ("details",
+                                     &bt->wire),
+          TALER_PQ_result_spec_end
+        };
+        if (GNUNET_YES !=
+            TALER_PQ_extract_result (result, rs, --rows))
+        {
+          GNUNET_break (0);
+          GNUNET_free (bt);
+          PQclear (result);
+          goto cleanup;
+        }
       }
       bt->reserve_pub = *reserve_pub;
-      /* FIXME: bt->wire not initialized! (#3817) */
       if (NULL != rh_tail)
       {
         rh_tail->next = GNUNET_new (struct TALER_MINTDB_ReserveHistory);
diff --git a/src/mintdb/test_mintdb.c b/src/mintdb/test_mintdb.c
index 74c1f66fe..56f5636d0 100644
--- a/src/mintdb/test_mintdb.c
+++ b/src/mintdb/test_mintdb.c
@@ -243,7 +243,8 @@ run (void *cls,
   struct TALER_MINTDB_CollectableBlindcoin *withdraw;
   struct TALER_MINTDB_Deposit deposit;
   struct TALER_MINTDB_Deposit deposit2;
-  struct json_t *wire;
+  json_t *wire;
+  json_t *just;
   const char * const json_wire_str =
       "{ \"type\":\"SEPA\", \
 \"IBAN\":\"DE67830654080004822650\",                    \
@@ -285,24 +286,28 @@ run (void *cls,
   amount.fraction = 1;
   strcpy (amount.currency, CURRENCY);
   result = 4;
+  just = json_loads ("{ \"justification\":\"1\" }", 0, NULL);
   FAILIF (GNUNET_OK !=
           plugin->reserves_in_insert (plugin->cls,
                                       session,
                                       &reserve_pub,
                                       &amount,
-				      "justification 1"));
+				      just));
+  json_decref (just);
   FAILIF (GNUNET_OK !=
           check_reserve (session,
                          &reserve_pub,
                          amount.value,
                          amount.fraction,
                          amount.currency));
+  just = json_loads ("{ \"justification\":\"2\" }", 0, NULL);
   FAILIF (GNUNET_OK !=
           plugin->reserves_in_insert (plugin->cls,
                                       session,
                                       &reserve_pub,
                                       &amount,
-				      "justification 2"));
+				      just));
+  json_decref (just);
   FAILIF (GNUNET_OK !=
           check_reserve (session,
                          &reserve_pub,
@@ -368,7 +373,7 @@ run (void *cls,
       FAILIF (1 != bt->amount.value);
       FAILIF (1 != bt->amount.fraction);
       FAILIF (0 != strcmp (CURRENCY, bt->amount.currency));
-      FAILIF (NULL != bt->wire); /* FIXME: write wire details to db */
+      FAILIF (NULL == bt->wire);
       break;
     case TALER_MINTDB_RO_WITHDRAW_COIN:
       withdraw = rh_head->details.withdraw;
diff --git a/src/pq/pq_helper.c b/src/pq/pq_helper.c
index f4b0c0109..8fd7e207b 100644
--- a/src/pq/pq_helper.c
+++ b/src/pq/pq_helper.c
@@ -174,8 +174,8 @@ TALER_PQ_query_param_json (const json_t *x)
  */
 struct TALER_PQ_ResultSpec
 TALER_PQ_result_spec_variable_size (const char *name,
-			  void **dst,
-			  size_t *sptr)
+                                    void **dst,
+                                    size_t *sptr)
 {
   struct TALER_PQ_ResultSpec res =
     { TALER_PQ_RF_VARSIZE_BLOB, (void *) (dst), 0, name, sptr };