diff --git a/src/exchange/taler-exchange-httpd_responses.c b/src/exchange/taler-exchange-httpd_responses.c
index c2a4a6cab..5233fc8e9 100644
--- a/src/exchange/taler-exchange-httpd_responses.c
+++ b/src/exchange/taler-exchange-httpd_responses.c
@@ -142,7 +142,7 @@ TEH_RESPONSE_compile_transaction_history (
 
         /* Age restriction is optional.  We communicate a NULL value to
          * JSON_PACK below */
-        if (! TALER_AgeHash_isZero (&melt->h_age_commitment))
+        if (! TALER_AgeHash_isNullOrZero (&melt->h_age_commitment))
           phac = &melt->h_age_commitment;
 
         if (0 !=
diff --git a/src/include/taler_crypto_lib.h b/src/include/taler_crypto_lib.h
index 026a0fda9..ab69d4dfb 100644
--- a/src/include/taler_crypto_lib.h
+++ b/src/include/taler_crypto_lib.h
@@ -312,10 +312,11 @@ struct TALER_AgeHash
 };
 
 extern const struct TALER_AgeHash TALER_AgeHash_zeroHash;
-#define TALER_AgeHash_isZero(ph) ((NULL == ph) || \
-                                  (0 == memcmp (ph, \
-                                                &TALER_AgeHash_zeroHash, \
-                                                sizeof(struct TALER_AgeHash))))
+#define TALER_AgeHash_isNullOrZero(ph) ((NULL == ph) || \
+                                        (0 == memcmp (ph, \
+                                                      &TALER_AgeHash_zeroHash, \
+                                                      sizeof(struct \
+                                                             TALER_AgeHash))))
 
 /**
  * @brief Type of public keys for Taler coins.  The same key material is used
diff --git a/src/lib/exchange_api_common.c b/src/lib/exchange_api_common.c
index a42cfa706..5f280b89b 100644
--- a/src/lib/exchange_api_common.c
+++ b/src/lib/exchange_api_common.c
@@ -593,7 +593,8 @@ TALER_EXCHANGE_verify_coin_history (
                                     &fee,
                                     &rc,
                                     h_denom_pub,
-                                    TALER_AgeHash_isZero (&h_age_commitment) ?
+                                    TALER_AgeHash_isNullOrZero (
+                                      &h_age_commitment) ?
                                     NULL : &h_age_commitment,
                                     coin_pub,
                                     &sig))
diff --git a/src/util/crypto.c b/src/util/crypto.c
index 12b2cc748..817ad3cd7 100644
--- a/src/util/crypto.c
+++ b/src/util/crypto.c
@@ -26,7 +26,7 @@
 #include <gcrypt.h>
 
 /**
- * Used in TALER_AgeHash_isZero for comparison
+ * Used in TALER_AgeHash_isNullOrZero for comparison
  */
 const struct TALER_AgeHash TALER_AgeHash_zeroHash = {0};