diff --git a/bin/named/include/named/globals.h b/bin/named/include/named/globals.h
index 6b978d1eb8..9ada34a768 100644
--- a/bin/named/include/named/globals.h
+++ b/bin/named/include/named/globals.h
@@ -111,6 +111,7 @@ EXTERN const char *named_g_chrootdir INIT(NULL);
 EXTERN bool named_g_foreground	     INIT(false);
 EXTERN bool named_g_logstderr	     INIT(false);
 EXTERN bool named_g_nosyslog	     INIT(false);
+EXTERN unsigned int named_g_logflags INIT(0);
 EXTERN const char *named_g_logfile   INIT(NULL);
 
 EXTERN const char *named_g_defaultsessionkeyfile INIT(NAMED_LOCALSTATEDIR
diff --git a/bin/named/log.c b/bin/named/log.c
index e477bd43ff..ffa916b569 100644
--- a/bin/named/log.c
+++ b/bin/named/log.c
@@ -79,6 +79,16 @@ named_log_setdefaultchannels(isc_logconfig_t *lcfg) {
 		isc_log_createchannel(lcfg, "default_debug", ISC_LOG_TOFILE,
 				      ISC_LOG_DYNAMIC, &destination,
 				      ISC_LOG_PRINTTIME | ISC_LOG_DEBUGONLY);
+	} else if (named_g_logstderr && (named_g_logflags != 0)) {
+		/*
+		 * If the option -g is given, but we also requested iso
+		 * timestamps, we'll still need to override the "default_debug"
+		 * logger with a new one.
+		 */
+		isc_log_createchannel(lcfg, "default_debug", ISC_LOG_TOFILEDESC,
+				      ISC_LOG_DYNAMIC,
+				      ISC_LOGDESTINATION_STDERR,
+				      ISC_LOG_PRINTTIME | named_g_logflags);
 	}
 
 	if (named_g_logfile != NULL) {
@@ -118,6 +128,16 @@ named_log_setsafechannels(isc_logconfig_t *lcfg) {
 		 * discarded a bit faster.
 		 */
 		isc_log_setdebuglevel(0);
+	} else if (named_g_logstderr && (named_g_logflags != 0)) {
+		/*
+		 * If the option -g is given, but we also requested iso
+		 * timestamps, we'll still need to override the "default_debug"
+		 * logger with a new one.
+		 */
+		isc_log_createchannel(lcfg, "default_debug", ISC_LOG_TOFILEDESC,
+				      ISC_LOG_DYNAMIC,
+				      ISC_LOGDESTINATION_STDERR,
+				      ISC_LOG_PRINTTIME | named_g_logflags);
 	} else {
 		isc_log_setdebuglevel(named_g_debuglevel);
 	}
diff --git a/bin/named/logconf.c b/bin/named/logconf.c
index c27e672b8a..f923722bf3 100644
--- a/bin/named/logconf.c
+++ b/bin/named/logconf.c
@@ -239,6 +239,8 @@ channel_fromconf(const cfg_obj_t *channel, isc_logconfig_t *logconfig) {
 				flags |= ISC_LOG_ISO8601;
 			} else if (strcasecmp(s, "iso8601-utc") == 0) {
 				flags |= ISC_LOG_ISO8601 | ISC_LOG_UTC;
+			} else if (strcasecmp(s, "iso8601-tzinfo") == 0) {
+				flags |= ISC_LOG_ISO8601 | ISC_LOG_TZINFO;
 			}
 		}
 	}
diff --git a/bin/named/main.c b/bin/named/main.c
index 98418bfbe3..91b46592b0 100644
--- a/bin/named/main.c
+++ b/bin/named/main.c
@@ -889,6 +889,8 @@ parse_command_line(int argc, char *argv[]) {
 		case 'g':
 			named_g_foreground = true;
 			named_g_logstderr = true;
+			named_g_logflags = ISC_LOG_PRINTTIME | ISC_LOG_ISO8601 |
+					   ISC_LOG_TZINFO;
 			break;
 		case 'L':
 			named_g_logfile = isc_commandline_argument;
diff --git a/bin/tests/system/cacheclean/tests.sh b/bin/tests/system/cacheclean/tests.sh
index 9b27ec2cf0..5359107508 100755
--- a/bin/tests/system/cacheclean/tests.sh
+++ b/bin/tests/system/cacheclean/tests.sh
@@ -101,7 +101,7 @@ digcomp --lc dig.out.ns2 knowngood.dig.out || status=1
 
 n=$((n + 1))
 echo_i "only one tcp socket was used ($n)"
-tcpclients=$(awk '$3 == "client" && $5 ~ /10.53.0.7#[0-9]*:/ {print $5}' ns2/named.run | sort | uniq -c | wc -l)
+tcpclients=$(awk '$2 == "client" && $4 ~ /10.53.0.7#[0-9]*:/ {print $4}' ns2/named.run | sort | uniq -c | wc -l)
 
 test $tcpclients -eq 1 || {
   status=1
diff --git a/bin/tests/system/checkconf/good-printtime.conf b/bin/tests/system/checkconf/good-printtime.conf
index 06bb7beece..3ec3e3b2f5 100644
--- a/bin/tests/system/checkconf/good-printtime.conf
+++ b/bin/tests/system/checkconf/good-printtime.conf
@@ -32,4 +32,8 @@ logging {
 		file "five.out";
 		print-time iso8601-utc;
 	};
+	channel six {
+		file "six.out";
+		print-time iso8601-tzinfo;
+	};
 };
diff --git a/bin/tests/system/kasp/tests.sh b/bin/tests/system/kasp/tests.sh
index f2479e6368..724785c5fb 100644
--- a/bin/tests/system/kasp/tests.sh
+++ b/bin/tests/system/kasp/tests.sh
@@ -2412,10 +2412,10 @@ _check_next_key_event() {
 
   # Get the latest next key event.
   if [ "${DYNAMIC}" = "yes" ]; then
-    _time=$(awk '{print $9}' <"keyevent.out.$ZONE.test$n" | tail -1)
+    _time=$(awk '{print $8}' <"keyevent.out.$ZONE.test$n" | tail -1)
   else
     # inline-signing zone adds "(signed)"
-    _time=$(awk '{print $10}' <"keyevent.out.$ZONE.test$n" | tail -1)
+    _time=$(awk '{print $9}' <"keyevent.out.$ZONE.test$n" | tail -1)
   fi
 
   # The next key event time must within threshold of the
diff --git a/bin/tests/system/mkeys/tests.sh b/bin/tests/system/mkeys/tests.sh
index b460121b04..952667df75 100644
--- a/bin/tests/system/mkeys/tests.sh
+++ b/bin/tests/system/mkeys/tests.sh
@@ -733,7 +733,7 @@ echo_i "check that trust-anchor-telemetry queries contain the correct key ($n)"
 ret=0
 # convert the hexadecimal key from the TAT query into decimal and
 # compare against the known key.
-tathex=$(grep "query '_ta-[0-9a-f][0-9a-f]*/NULL/IN' approved" ns1/named.run | awk '{print $6; exit 0}' | sed -e 's/(_ta-\([0-9a-f][0-9a-f]*\)):/\1/') || true
+tathex=$(grep "query '_ta-[0-9a-f][0-9a-f]*/NULL/IN' approved" ns1/named.run | awk '{print $5; exit 0}' | sed -e 's/(_ta-\([0-9a-f][0-9a-f]*\)):/\1/') || true
 tatkey=$($PERL -e 'printf("%d\n", hex(@ARGV[0]));' "$tathex")
 realkey=$(rndccmd 10.53.0.2 secroots - | sed -n "s#.*${DEFAULT_ALGORITHM}/\([0-9][0-9]*\) ; .*managed.*#\1#p")
 [ "$tatkey" -eq "$realkey" ] || ret=1
diff --git a/bin/tests/system/notify/tests.sh b/bin/tests/system/notify/tests.sh
index 08ee243562..a827e6da5c 100644
--- a/bin/tests/system/notify/tests.sh
+++ b/bin/tests/system/notify/tests.sh
@@ -65,7 +65,8 @@ test_end
 
 test_start "checking startup notify rate limit"
 awk '/x[0-9].*sending notify to/ {
-	split($2, a, ":");
+  split($1, ts, "T");
+	split(ts[2], a, ":");
 	this = a[1] * 3600 + a[2] * 60 + a[3];
 	if (lasta1 && lasta1 > a[1]) {
 		fix = 3600 * 24;
diff --git a/bin/tests/system/start.pl b/bin/tests/system/start.pl
index 67c33b86f2..f8faac91a7 100755
--- a/bin/tests/system/start.pl
+++ b/bin/tests/system/start.pl
@@ -373,9 +373,9 @@ sub count_running_lines {
 	# the shell *ought* to have created the file immediately, but this
 	# logic allows the creation to be delayed without issues
 	if (open(my $fh, "<", $runfile)) {
-		# the two non-whitespace blobs should be the date and time
+		# the whitespace blob should be an ISO timestamp
 		# but we don't care about them really, only that they are there
-		return scalar(grep /^\S+ \S+ running\R/, <$fh>);
+		return scalar(grep /^\S+[ T]\S+ running\R/, <$fh>);
 	} else {
 		return 0;
 	}
diff --git a/bin/tests/system/xfer/tests.sh b/bin/tests/system/xfer/tests.sh
index f75e1d9caf..5818870b60 100755
--- a/bin/tests/system/xfer/tests.sh
+++ b/bin/tests/system/xfer/tests.sh
@@ -528,7 +528,7 @@ $RNDCCMD 10.53.0.7 refresh edns-expire 2>&1 | sed 's/^/ns7 /' | cat_i
 sleep 10
 
 # there may be multiple log entries so get the last one.
-expire=$(awk '/edns-expire\/IN: got EDNS EXPIRE of/ { x=$9 } END { print x }' ns7/named.run)
+expire=$(awk '/edns-expire\/IN: got EDNS EXPIRE of/ { x=$8 } END { print x }' ns7/named.run)
 test ${expire:-0} -gt 0 -a ${expire:-0} -lt 1814400 || {
   echo_i "failed (expire=${expire:-0})"
   status=$((status + 1))
diff --git a/doc/arm/reference.rst b/doc/arm/reference.rst
index 1c363f6662..119c8686fa 100644
--- a/doc/arm/reference.rst
+++ b/doc/arm/reference.rst
@@ -812,13 +812,16 @@ what messages to print.
    :short: Specifies the time format for log messages.
 
    :any:`print-time` can be set to ``yes``, ``no``, or a time format
-   specifier, which may be one of ``local``, ``iso8601``, or
-   ``iso8601-utc``. If set to ``no``, the date and time are not
-   logged. If set to ``yes`` or ``local``, the date and time are logged in
-   a human-readable format, using the local time zone. If set to
-   ``iso8601``, the local time is logged in ISO 8601 format. If set to
+   specifier, which may be one of ``local``, ``iso8601``, ``iso8601-utc``
+   or ``iso8601-tzinfo``.  If set to ``no``, the date and time are
+   not logged. If set to ``yes`` or ``local``, the date and time are
+   logged in a human-readable format, using the local time zone. If
+   set to ``iso8601``, the local time is logged in ISO 8601 format,
+   but no timezone information is included in the timestamp.  If set to
    ``iso8601-utc``, the date and time are logged in ISO 8601 format,
-   with time zone set to UTC. The default is ``no``.
+   with time zone set to UTC. If set to ``iso8601-tzinfo``, the local
+   time is logged in ISO 8601 format, with timezone information included
+   at the end of the timestamp. The default is ``no``.
 
    :any:`print-time` may be specified for a :any:`syslog` channel, but it is
    usually pointless since :any:`syslog` also logs the date and time.
diff --git a/doc/misc/options b/doc/misc/options
index b3714e4d38..4e54305b58 100644
--- a/doc/misc/options
+++ b/doc/misc/options
@@ -57,7 +57,7 @@ logging {
 		null;
 		print-category <boolean>;
 		print-severity <boolean>;
-		print-time ( iso8601 | iso8601-utc | local | <boolean> );
+		print-time ( iso8601 | iso8601-utc | iso8601-tzinfo | local | <boolean> );
 		severity <log_severity>;
 		stderr;
 		syslog [ <syslog_facility> ];
diff --git a/lib/isc/include/isc/log.h b/lib/isc/include/isc/log.h
index c7d02cce96..f7b357c8fb 100644
--- a/lib/isc/include/isc/log.h
+++ b/lib/isc/include/isc/log.h
@@ -72,6 +72,7 @@ typedef struct isc_logconfig isc_logconfig_t; /*%< Log Configuration */
 #define ISC_LOG_OPENERR	      0x08000 /* internal */
 #define ISC_LOG_ISO8601	      0x10000 /* if PRINTTIME, use ISO8601 */
 #define ISC_LOG_UTC	      0x20000 /* if PRINTTIME, use UTC */
+#define ISC_LOG_TZINFO	      0x40000 /* if PRINTTIME, output TZ info */
 /*@}*/
 
 /*@{*/
diff --git a/lib/isc/include/isc/time.h b/lib/isc/include/isc/time.h
index ad74be9270..f08cd2e112 100644
--- a/lib/isc/include/isc/time.h
+++ b/lib/isc/include/isc/time.h
@@ -395,20 +395,6 @@ isc_time_parsehttptimestamp(char *input, isc_time_t *t);
  *\li      'buf' and 't' are not NULL.
  */
 
-void
-isc_time_formatISO8601L(const isc_time_t *t, char *buf, unsigned int len);
-/*%<
- * Format the time 't' into the buffer 'buf' of length 'len',
- * using the ISO8601 format: "yyyy-mm-ddThh:mm:ss"
- * If the text does not fit in the buffer, the result is indeterminate,
- * but is always guaranteed to be null terminated.
- *
- *  Requires:
- *\li      'len' > 0
- *\li      'buf' points to an array of at least len chars
- *
- */
-
 void
 isc_time_formatISO8601Lms(const isc_time_t *t, char *buf, unsigned int len);
 /*%<
@@ -424,10 +410,10 @@ isc_time_formatISO8601Lms(const isc_time_t *t, char *buf, unsigned int len);
  */
 
 void
-isc_time_formatISO8601Lus(const isc_time_t *t, char *buf, unsigned int len);
+isc_time_formatISO8601TZms(const isc_time_t *t, char *buf, unsigned int len);
 /*%<
  * Format the time 't' into the buffer 'buf' of length 'len',
- * using the ISO8601 format: "yyyy-mm-ddThh:mm:ss.ssssss"
+ * using the ISO8601 format: "yyyy-mm-ddThh:mm:ss.sss+hhmm"
  * If the text does not fit in the buffer, the result is indeterminate,
  * but is always guaranteed to be null terminated.
  *
diff --git a/lib/isc/log.c b/lib/isc/log.c
index 53dcb47921..7b65a6094c 100644
--- a/lib/isc/log.c
+++ b/lib/isc/log.c
@@ -477,7 +477,7 @@ isc_log_createchannel(isc_logconfig_t *lcfg, const char *name,
 	isc_mem_t *mctx;
 	unsigned int permitted = ISC_LOG_PRINTALL | ISC_LOG_DEBUGONLY |
 				 ISC_LOG_BUFFERED | ISC_LOG_ISO8601 |
-				 ISC_LOG_UTC;
+				 ISC_LOG_UTC | ISC_LOG_TZINFO;
 
 	REQUIRE(VALID_CONFIG(lcfg));
 	REQUIRE(name != NULL);
@@ -486,6 +486,7 @@ isc_log_createchannel(isc_logconfig_t *lcfg, const char *name,
 	REQUIRE(destination != NULL || type == ISC_LOG_TONULL);
 	REQUIRE(level >= ISC_LOG_CRITICAL);
 	REQUIRE((flags & ~permitted) == 0);
+	REQUIRE(!(flags & ISC_LOG_UTC) || !(flags & ISC_LOG_TZINFO));
 
 	/* FIXME: find duplicate names? */
 
@@ -1256,13 +1257,14 @@ isc_log_doit(isc_logcategory_t category, isc_logmodule_t module, int level,
 	     const char *format, va_list args) {
 	int syslog_level;
 	const char *time_string;
-	char local_time[64];
-	char iso8601z_string[64];
-	char iso8601l_string[64];
+	char local_time[64] = { 0 };
+	char iso8601z_string[64] = { 0 };
+	char iso8601l_string[64] = { 0 };
+	char iso8601tz_string[64] = { 0 };
 	char level_string[24] = { 0 };
 	struct stat statbuf;
 	bool matched = false;
-	bool printtime, iso8601, utc, printtag, printcolon;
+	bool printtime, iso8601, utc, tzinfo, printtag, printcolon;
 	bool printcategory, printmodule, printlevel, buffered;
 	isc_logchannel_t *channel;
 	isc_logchannellist_t *category_channels;
@@ -1280,10 +1282,6 @@ isc_log_doit(isc_logcategory_t category, isc_logmodule_t module, int level,
 		return;
 	}
 
-	local_time[0] = '\0';
-	iso8601l_string[0] = '\0';
-	iso8601z_string[0] = '\0';
-
 	rcu_read_lock();
 	LOCK(&isc__lctx->lock);
 
@@ -1368,6 +1366,8 @@ isc_log_doit(isc_logcategory_t category, isc_logmodule_t module, int level,
 						 sizeof(iso8601z_string));
 			isc_time_formatISO8601Lms(&isctime, iso8601l_string,
 						  sizeof(iso8601l_string));
+			isc_time_formatISO8601TZms(&isctime, iso8601tz_string,
+						   sizeof(iso8601tz_string));
 		}
 
 		if ((channel->flags & ISC_LOG_PRINTLEVEL) != 0 &&
@@ -1396,6 +1396,7 @@ isc_log_doit(isc_logcategory_t category, isc_logmodule_t module, int level,
 		}
 
 		utc = ((channel->flags & ISC_LOG_UTC) != 0);
+		tzinfo = ((channel->flags & ISC_LOG_TZINFO) != 0);
 		iso8601 = ((channel->flags & ISC_LOG_ISO8601) != 0);
 		printtime = ((channel->flags & ISC_LOG_PRINTTIME) != 0);
 		printtag = ((channel->flags &
@@ -1412,6 +1413,8 @@ isc_log_doit(isc_logcategory_t category, isc_logmodule_t module, int level,
 			if (iso8601) {
 				if (utc) {
 					time_string = iso8601z_string;
+				} else if (tzinfo) {
+					time_string = iso8601tz_string;
 				} else {
 					time_string = iso8601l_string;
 				}
diff --git a/lib/isc/time.c b/lib/isc/time.c
index cff1764554..1a4eae228d 100644
--- a/lib/isc/time.c
+++ b/lib/isc/time.c
@@ -382,22 +382,6 @@ isc_time_parsehttptimestamp(char *buf, isc_time_t *t) {
 	return (ISC_R_SUCCESS);
 }
 
-void
-isc_time_formatISO8601L(const isc_time_t *t, char *buf, unsigned int len) {
-	time_t now;
-	unsigned int flen;
-	struct tm tm;
-
-	REQUIRE(t != NULL);
-	INSIST(t->nanoseconds < NS_PER_SEC);
-	REQUIRE(buf != NULL);
-	REQUIRE(len > 0);
-
-	now = (time_t)t->seconds;
-	flen = strftime(buf, len, "%Y-%m-%dT%H:%M:%S", localtime_r(&now, &tm));
-	INSIST(flen < len);
-}
-
 void
 isc_time_formatISO8601Lms(const isc_time_t *t, char *buf, unsigned int len) {
 	time_t now;
@@ -419,7 +403,9 @@ isc_time_formatISO8601Lms(const isc_time_t *t, char *buf, unsigned int len) {
 }
 
 void
-isc_time_formatISO8601Lus(const isc_time_t *t, char *buf, unsigned int len) {
+isc_time_formatISO8601TZms(const isc_time_t *t, char *buf, unsigned int len) {
+	char strftime_buf[64] = { 0 };
+	char ms_buf[8] = { 0 };
 	time_t now;
 	unsigned int flen;
 	struct tm tm;
@@ -430,14 +416,20 @@ isc_time_formatISO8601Lus(const isc_time_t *t, char *buf, unsigned int len) {
 	REQUIRE(len > 0);
 
 	now = (time_t)t->seconds;
-	flen = strftime(buf, len, "%Y-%m-%dT%H:%M:%S", localtime_r(&now, &tm));
-	INSIST(flen < len);
-	if (flen > 0U && len - flen >= 6) {
-		snprintf(buf + flen, len - flen, ".%06u",
-			 t->nanoseconds / NS_PER_US);
-	}
-}
+	flen = strftime(strftime_buf, len, "%Y-%m-%dT%H:%M:%S.xxx%z",
+			localtime_r(&now, &tm));
+	snprintf(ms_buf, sizeof(ms_buf), ".%03u", t->nanoseconds / NS_PER_MS);
 
+	INSIST(flen < len);
+	size_t local_date_len = sizeof("yyyy-mm-ddThh:mm:ss") - 1ul;
+	size_t ms_date_len = local_date_len + 4;
+
+	memmove(buf, strftime_buf, local_date_len);
+	memmove(buf + local_date_len, ms_buf, 4);
+	memmove(buf + ms_date_len, strftime_buf + ms_date_len, 3);
+	buf[ms_date_len + 3] = ':';
+	memmove(buf + ms_date_len + 4, strftime_buf + ms_date_len + 3, 3);
+}
 void
 isc_time_formatISO8601(const isc_time_t *t, char *buf, unsigned int len) {
 	time_t now;
diff --git a/lib/isccfg/namedconf.c b/lib/isccfg/namedconf.c
index dbb787e518..e6aace10db 100644
--- a/lib/isccfg/namedconf.c
+++ b/lib/isccfg/namedconf.c
@@ -2631,8 +2631,8 @@ static cfg_type_t cfg_type_server = { "server",	     cfg_parse_netprefix_map,
  *  - There must exactly one of file/syslog/null/stderr
  */
 
-static const char *printtime_enums[] = { "iso8601", "iso8601-utc", "local",
-					 NULL };
+static const char *printtime_enums[] = { "iso8601", "iso8601-utc",
+					 "iso8601-tzinfo", "local", NULL };
 static isc_result_t
 parse_printtime(cfg_parser_t *pctx, const cfg_type_t *type, cfg_obj_t **ret) {
 	return (cfg_parse_enum_or_other(pctx, type, &cfg_type_boolean, ret));
diff --git a/tests/isc/time_test.c b/tests/isc/time_test.c
index 18b42e5098..d3a7c016f4 100644
--- a/tests/isc/time_test.c
+++ b/tests/isc/time_test.c
@@ -256,9 +256,9 @@ ISC_RUN_TEST_IMPL(isc_time_formatISO8601us_test) {
 	assert_string_equal(buf, "2015-12-13T09:46:40.123456Z");
 }
 
-/* print local time in ISO8601 */
+/* print local time in ISO8601 with milliseconds and timezone */
 
-ISC_RUN_TEST_IMPL(isc_time_formatISO8601L_test) {
+ISC_RUN_TEST_IMPL(isc_time_formatISO8601TZms_test) {
 	isc_time_t t;
 	char buf[64];
 
@@ -267,28 +267,34 @@ ISC_RUN_TEST_IMPL(isc_time_formatISO8601L_test) {
 	setenv("TZ", "America/Los_Angeles", 1);
 	t = isc_time_now();
 
-	/* check formatting: yyyy-mm-ddThh:mm:ss */
+	/* check formatting: yyyy-mm-ddThh:mm:ss.sss */
 	memset(buf, 'X', sizeof(buf));
-	isc_time_formatISO8601L(&t, buf, sizeof(buf));
-	assert_int_equal(strlen(buf), 19);
+	buf[63] = '\0';
+	isc_time_formatISO8601TZms(&t, buf, sizeof(buf));
+	assert_int_equal(strlen(buf), strlen("yyyy-mm-ddThh:mm:ss.sss+hh:mm"));
+
 	assert_int_equal(buf[4], '-');
 	assert_int_equal(buf[7], '-');
 	assert_int_equal(buf[10], 'T');
 	assert_int_equal(buf[13], ':');
 	assert_int_equal(buf[16], ':');
+	assert_int_equal(buf[19], '.');
+
+	size_t plus_minus[2] = { '+', '-' };
+	assert_in_set(buf[23], plus_minus, sizeof(plus_minus));
+	assert_int_equal(buf[26], ':');
 
 	/* check time conversion correctness */
 	memset(buf, 'X', sizeof(buf));
 	isc_time_settoepoch(&t);
-	isc_time_formatISO8601L(&t, buf, sizeof(buf));
-	assert_string_equal(buf, "1969-12-31T16:00:00");
+	isc_time_formatISO8601Lms(&t, buf, sizeof(buf));
+	assert_string_equal(buf, "1969-12-31T16:00:00.000");
 
 	memset(buf, 'X', sizeof(buf));
 	isc_time_set(&t, 1450000000, 123000000);
-	isc_time_formatISO8601L(&t, buf, sizeof(buf));
-	assert_string_equal(buf, "2015-12-13T01:46:40");
+	isc_time_formatISO8601Lms(&t, buf, sizeof(buf));
+	assert_string_equal(buf, "2015-12-13T01:46:40.123");
 }
-
 /* print local time in ISO8601 with milliseconds */
 
 ISC_RUN_TEST_IMPL(isc_time_formatISO8601Lms_test) {
@@ -323,40 +329,6 @@ ISC_RUN_TEST_IMPL(isc_time_formatISO8601Lms_test) {
 	assert_string_equal(buf, "2015-12-13T01:46:40.123");
 }
 
-/* print local time in ISO8601 with microseconds */
-
-ISC_RUN_TEST_IMPL(isc_time_formatISO8601Lus_test) {
-	isc_time_t t;
-	char buf[64];
-
-	UNUSED(state);
-
-	setenv("TZ", "America/Los_Angeles", 1);
-	t = isc_time_now_hires();
-
-	/* check formatting: yyyy-mm-ddThh:mm:ss.ssssss */
-	memset(buf, 'X', sizeof(buf));
-	isc_time_formatISO8601Lus(&t, buf, sizeof(buf));
-	assert_int_equal(strlen(buf), 26);
-	assert_int_equal(buf[4], '-');
-	assert_int_equal(buf[7], '-');
-	assert_int_equal(buf[10], 'T');
-	assert_int_equal(buf[13], ':');
-	assert_int_equal(buf[16], ':');
-	assert_int_equal(buf[19], '.');
-
-	/* check time conversion correctness */
-	memset(buf, 'X', sizeof(buf));
-	isc_time_settoepoch(&t);
-	isc_time_formatISO8601Lus(&t, buf, sizeof(buf));
-	assert_string_equal(buf, "1969-12-31T16:00:00.000000");
-
-	memset(buf, 'X', sizeof(buf));
-	isc_time_set(&t, 1450000000, 123456000);
-	isc_time_formatISO8601Lus(&t, buf, sizeof(buf));
-	assert_string_equal(buf, "2015-12-13T01:46:40.123456");
-}
-
 /* print UTC time as yyyymmddhhmmsssss */
 
 ISC_RUN_TEST_IMPL(isc_time_formatshorttimestamp_test) {
@@ -393,9 +365,8 @@ ISC_TEST_ENTRY(isc_time_parsehttptimestamp_test)
 ISC_TEST_ENTRY(isc_time_formatISO8601_test)
 ISC_TEST_ENTRY(isc_time_formatISO8601ms_test)
 ISC_TEST_ENTRY(isc_time_formatISO8601us_test)
-ISC_TEST_ENTRY(isc_time_formatISO8601L_test)
 ISC_TEST_ENTRY(isc_time_formatISO8601Lms_test)
-ISC_TEST_ENTRY(isc_time_formatISO8601Lus_test)
+ISC_TEST_ENTRY(isc_time_formatISO8601TZms_test)
 ISC_TEST_ENTRY(isc_time_formatshorttimestamp_test)
 
 ISC_TEST_LIST_END