diff --git a/CHANGES b/CHANGES
index 4bddb6e51b..50a1386d49 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,7 @@
+6048.	[bug]		Fix a log message error in dns_catz_update_from_db(),
+			where serials with values of 2^31 or larger were logged
+			incorrectly as negative numbers. [GL #3742]
+
 6047.	[bug]		Try the next server instead of trying the same
 			server again on an outgoing query timeout.
 			[GL #3637]
diff --git a/bin/tests/system/catz/ns3/catalog.example.db.in b/bin/tests/system/catz/ns3/catalog.example.db.in
index a0bab0dfe2..eccb4f1004 100644
--- a/bin/tests/system/catz/ns3/catalog.example.db.in
+++ b/bin/tests/system/catz/ns3/catalog.example.db.in
@@ -9,6 +9,6 @@
 ; See the COPYRIGHT file distributed with this work for additional
 ; information regarding copyright ownership.
 
-@ 3600 SOA . . 1 86400 3600 86400 3600
+@ 3600 SOA . . 2670950424 86400 3600 86400 3600
 @ 3600 IN NS invalid.
 version IN TXT "1"
diff --git a/bin/tests/system/catz/tests.sh b/bin/tests/system/catz/tests.sh
index ee95d2e124..09c7ba5d04 100644
--- a/bin/tests/system/catz/tests.sh
+++ b/bin/tests/system/catz/tests.sh
@@ -382,6 +382,7 @@ status=$((status+ret))
 n=$((n+1))
 echo_i "waiting for secondary to sync up ($n)"
 ret=0
+wait_for_message ns2/named.run "catz: updating catalog zone 'catalog2.example' with serial 2670950425" &&
 wait_for_message ns2/named.run "catz: adding zone 'dom2.example' from catalog 'catalog1.example'" &&
 wait_for_message ns2/named.run "catz: adding zone 'dom3.example' from catalog 'catalog1.example'" &&
 wait_for_message ns2/named.run "catz: adding zone 'dom4.example' from catalog 'catalog2.example'" &&
diff --git a/lib/dns/catz.c b/lib/dns/catz.c
index fd24410594..b755e6cce5 100644
--- a/lib/dns/catz.c
+++ b/lib/dns/catz.c
@@ -2167,8 +2167,8 @@ dns_catz_update_from_db(dns_db_t *db, dns_catz_zones_t *catzs) {
 
 	isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_MASTER,
 		      ISC_LOG_INFO,
-		      "catz: updating catalog zone '%s' with serial %d", bname,
-		      vers);
+		      "catz: updating catalog zone '%s' with serial %" PRIu32,
+		      bname, vers);
 
 	result = dns_catz_new_zone(catzs, &newzone, &db->origin);
 	if (result != ISC_R_SUCCESS) {