diff --git a/src/include/taler_exchange_service.h b/src/include/taler_exchange_service.h
index 2dd220293..e1f632a6f 100644
--- a/src/include/taler_exchange_service.h
+++ b/src/include/taler_exchange_service.h
@@ -1449,7 +1449,7 @@ TALER_EXCHANGE_withdraw (
   struct TALER_EXCHANGE_Handle *exchange,
   const struct TALER_EXCHANGE_DenomPublicKey *pk,
   const struct TALER_ReservePrivateKeyP *reserve_priv,
-  const struct TALER_PlanchetSecretsP *ps,
+  struct TALER_PlanchetSecretsP *ps,
   TALER_EXCHANGE_WithdrawCallback res_cb,
   void *res_cb_cls);
 
diff --git a/src/lib/exchange_api_withdraw.c b/src/lib/exchange_api_withdraw.c
index 5834306eb..a8bce5e71 100644
--- a/src/lib/exchange_api_withdraw.c
+++ b/src/lib/exchange_api_withdraw.c
@@ -170,7 +170,7 @@ TALER_EXCHANGE_withdraw (
   struct TALER_EXCHANGE_Handle *exchange,
   const struct TALER_EXCHANGE_DenomPublicKey *pk,
   const struct TALER_ReservePrivateKeyP *reserve_priv,
-  const struct TALER_PlanchetSecretsP *ps,
+  struct TALER_PlanchetSecretsP *ps,
   TALER_EXCHANGE_WithdrawCallback res_cb,
   void *res_cb_cls)
 {