diff --git a/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts b/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts
index 01d2677dc..c1a761fb6 100644
--- a/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts
+++ b/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts
@@ -723,7 +723,7 @@ export const nativeCryptoR: TalerCryptoInterfaceR = {
         maybeAcp = await AgeRestriction.restrictionCommitSeeded(
           denomPub.age_mask,
           age,
-          stringToBytes(req.secretSeed)
+          stringToBytes(req.secretSeed),
         );
         maybeAgeCommitmentHash = AgeRestriction.hashCommitment(
           maybeAcp.commitment,
@@ -1127,6 +1127,8 @@ export const nativeCryptoR: TalerCryptoInterfaceR = {
       // All zeros.
       hAgeCommitment = new Uint8Array(32);
     }
+    // FIXME: Actually allow passing user data here!
+    const walletDataHash = new Uint8Array(64);
     let d: Uint8Array;
     if (depositInfo.denomKeyType === DenomKeyType.Rsa) {
       d = buildSigPS(TalerSignaturePurpose.WALLET_COIN_DEPOSIT)
@@ -1140,6 +1142,7 @@ export const nativeCryptoR: TalerCryptoInterfaceR = {
         .put(amountToBuffer(depositInfo.spendAmount))
         .put(amountToBuffer(depositInfo.feeDeposit))
         .put(decodeCrock(depositInfo.merchantPub))
+        .put(walletDataHash)
         .build();
     } else {
       throw Error("unsupported exchange protocol version");