diff --git a/src/include/taler_error_codes.h b/src/include/taler_error_codes.h
index 871ec2bfe..55cdbacbd 100644
--- a/src/include/taler_error_codes.h
+++ b/src/include/taler_error_codes.h
@@ -1442,6 +1442,7 @@ enum TALER_ErrorCode
    * The amount to be refunded is inconsistent: either is lower than
    * the previous amount being awarded, or it is too big to be paid back.
    * In this second case, the fault stays on the business dept. side.
+   * Returned with an HTTP status of #MHD_HTTP_CONFLICT.
    */
   TALER_EC_REFUND_INCONSISTENT_AMOUNT = 2602,
 
diff --git a/src/include/taler_mhd_lib.h b/src/include/taler_mhd_lib.h
index 17783f1c4..cdbc8d290 100644
--- a/src/include/taler_mhd_lib.h
+++ b/src/include/taler_mhd_lib.h
@@ -143,6 +143,40 @@ TALER_MHD_reply_with_error (struct MHD_Connection *connection,
                             const char *hint);
 
 
+/**
+ * Make JSON response object.
+ *
+ * @param json the json object
+ * @return MHD response object
+ */
+struct MHD_Response *
+TALER_MHD_make_json (const json_t *json);
+
+
+/**
+ * Make JSON response object.
+ *
+ * @param fmt format string for pack
+ * @param ... varargs
+ * @return MHD response object
+ */
+struct MHD_Response *
+TALER_MHD_make_json_pack (const char *fmt,
+                          ...);
+
+
+/**
+ * Create a response indicating an internal error.
+ *
+ * @param ec error code to return
+ * @param hint hint about the internal error's nature
+ * @return a MHD response object
+ */
+struct MHD_Response *
+TALER_MHD_make_error (enum TALER_ErrorCode ec,
+                      const char *hint);
+
+
 /**
  * Send a response indicating that the request was too big.
  *
@@ -338,4 +372,22 @@ TALER_MHD_open_unix_path (const char *unix_path,
                           mode_t unix_mode);
 
 
+/**
+ * Bind a listen socket to the UNIX domain path
+ * or the TCP port and IP address as specified
+ * in @a cfg in section @a section.  IF only a
+ * port was specified, set @a port and return -1.
+ * Otherwise, return the bound file descriptor.
+ *
+ * @param cfg configuration to parse
+ * @param section configuration section to use
+ * @param port[out] port to set, if TCP without BINDTO
+ * @return -1 and a port of zero on error, otherwise
+ *    either -1 and a port, or a bound stream socket
+ */
+int
+TALER_MHD_bind (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                const char *section,
+                uint16_t *port);
+
 #endif
diff --git a/src/mhd/mhd_config.c b/src/mhd/mhd_config.c
index afaceae40..d4b0e9795 100644
--- a/src/mhd/mhd_config.c
+++ b/src/mhd/mhd_config.c
@@ -285,3 +285,112 @@ TALER_MHD_open_unix_path (const char *unix_path,
   GNUNET_NETWORK_socket_free_memory_only_ (nh);
   return fd;
 }
+
+
+/**
+ * Bind a listen socket to the UNIX domain path
+ * or the TCP port and IP address as specified
+ * in @a cfg in section @a section.  IF only a
+ * port was specified, set @a port and return -1.
+ * Otherwise, return the bound file descriptor.
+ *
+ * @param cfg configuration to parse
+ * @param section configuration section to use
+ * @param port[out] port to set, if TCP without BINDTO
+ * @return -1 and a port of zero on error, otherwise
+ *    either -1 and a port, or a bound stream socket
+ */
+int
+TALER_MHD_bind (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                const char *section,
+                uint16_t *port)
+{
+  char *bind_to;
+  char *serve_unixpath;
+  mode_t unixpath_mode;
+  int fh;
+  char port_str[6];
+  struct addrinfo hints;
+  struct addrinfo *res;
+  int ec;
+  struct GNUNET_NETWORK_Handle *nh;
+
+  *port = 0;
+  if (GNUNET_OK !=
+      TALER_MHD_parse_config (cfg,
+                              section,
+                              port,
+                              &serve_unixpath,
+                              &unixpath_mode))
+    return -1;
+  if (NULL != serve_unixpath)
+    return TALER_MHD_open_unix_path (serve_unixpath,
+                                     unixpath_mode);
+  if (GNUNET_OK !=
+      GNUNET_CONFIGURATION_get_value_string (cfg,
+                                             section,
+                                             "BIND_TO",
+                                             &bind_to))
+    return -1; /* only set port */
+  /* let's have fun binding... */
+  GNUNET_snprintf (port_str,
+                   sizeof (port_str),
+                   "%u",
+                   (unsigned int) *port);
+  *port = 0; /* do NOT return port in case of errors */
+  memset (&hints, 0, sizeof (hints));
+  hints.ai_family = AF_UNSPEC;
+  hints.ai_socktype = SOCK_STREAM;
+  hints.ai_protocol = IPPROTO_TCP;
+  hints.ai_flags = AI_PASSIVE
+#ifdef AI_IDN
+                   | AI_IDN
+#endif
+  ;
+  if (0 !=
+      (ec = getaddrinfo (bind_to,
+                         port_str,
+                         &hints,
+                         &res)))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Failed to resolve BIND_TO address `%s': %s\n",
+                bind_to,                  gai_strerror (ec));
+    GNUNET_free (bind_to);
+    return -1;
+  }
+  GNUNET_free (bind_to);
+
+  if (NULL == (nh = GNUNET_NETWORK_socket_create (res->ai_family,
+                                                  res->ai_socktype,
+                                                  res->ai_protocol)))
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "socket");
+    freeaddrinfo (res);
+    return -1;
+  }
+  if (GNUNET_OK !=
+      GNUNET_NETWORK_socket_bind (nh,
+                                  res->ai_addr,
+                                  res->ai_addrlen))
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "bind");
+    freeaddrinfo (res);
+    return -1;
+  }
+  freeaddrinfo (res);
+  if (GNUNET_OK !=
+      GNUNET_NETWORK_socket_listen (nh,
+                                    UNIX_BACKLOG))
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "listen");
+    GNUNET_SCHEDULER_shutdown ();
+    return -1;
+  }
+  fh = GNUNET_NETWORK_get_fd (nh);
+  GNUNET_NETWORK_socket_free_memory_only_ (nh);
+  return fh;
+}
diff --git a/src/mhd/mhd_responses.c b/src/mhd/mhd_responses.c
index e1609d996..3642e7d54 100644
--- a/src/mhd/mhd_responses.c
+++ b/src/mhd/mhd_responses.c
@@ -151,6 +151,43 @@ TALER_MHD_body_compress (void **buf,
 }
 
 
+/**
+ * Make JSON response object.
+ *
+ * @param json the json object
+ * @return MHD response object
+ */
+struct MHD_Response *
+TALER_MHD_make_json (const json_t *json)
+{
+  struct MHD_Response *resp;
+  char *json_str;
+
+  json_str = json_dumps (json,
+                         JSON_INDENT (2));
+  if (NULL == json_str)
+  {
+    GNUNET_break (0);
+    return NULL;
+  }
+  resp = MHD_create_response_from_buffer (strlen (json_str),
+                                          json_str,
+                                          MHD_RESPMEM_MUST_FREE);
+  if (NULL == resp)
+  {
+    free (json_str);
+    GNUNET_break (0);
+    return NULL;
+  }
+  TALER_MHD_add_global_headers (resp);
+  GNUNET_break (MHD_YES ==
+                MHD_add_response_header (resp,
+                                         MHD_HTTP_HEADER_CONTENT_TYPE,
+                                         "application/json"));
+  return resp;
+}
+
+
 /**
  * Send JSON object as response.
  *
@@ -267,6 +304,60 @@ TALER_MHD_reply_json_pack (struct MHD_Connection *connection,
 }
 
 
+/**
+ * Make JSON response object.
+ *
+ * @param fmt format string for pack
+ * @param ... varargs
+ * @return MHD response object
+ */
+struct MHD_Response *
+TALER_MHD_make_json_pack (const char *fmt,
+                          ...)
+{
+  json_t *json;
+  va_list argp;
+  struct MHD_Response *ret;
+  json_error_t jerror;
+
+  va_start (argp, fmt);
+  json = json_vpack_ex (&jerror,
+                        0,
+                        fmt,
+                        argp);
+  va_end (argp);
+  if (NULL == json)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Failed to pack JSON with format `%s': %s\n",
+                fmt,
+                jerror.text);
+    GNUNET_break (0);
+    return MHD_NO;
+  }
+  ret = TALER_MHD_make_json (json);
+  json_decref (json);
+  return ret;
+}
+
+
+/**
+ * Create a response indicating an internal error.
+ *
+ * @param ec error code to return
+ * @param hint hint about the internal error's nature
+ * @return a MHD response object
+ */
+struct MHD_Response *
+TALER_MHD_make_error (enum TALER_ErrorCode ec,
+                      const char *hint)
+{
+  return TALER_MHD_make_json_pack ("{s:I, s:s}",
+                                   "code", (json_int_t) ec,
+                                   "hint", hint);
+}
+
+
 /**
  * Send a response indicating an error.
  *