diff --git a/usr.bin/calendar/calendars/calendar.computer b/usr.bin/calendar/calendars/calendar.computer
index b153349a049d..e8b22b482a19 100644
--- a/usr.bin/calendar/calendars/calendar.computer
+++ b/usr.bin/calendar/calendars/calendar.computer
@@ -29,7 +29,7 @@
 03/14	LISP introduced, 1960
 03/28	DEC announces PDP-11, 1970
 03/31	Eckert-Mauchly Computer Corp. founded, Phila, 1946
-04/01	Yourdon, Inc. founded, 1974  (It figures.)
+04/01	Yourdon, Inc. founded, 1974 (It figures.)
 04/03	IBM 701 introduced, 1953
 04/04	Tandy Corp. acquires Radio Shack, 1963 (9 stores)
 04/07	IBM announces System/360, 1964
@@ -55,6 +55,7 @@
 	Temple Univ., Phila, 1948, for symbolic differentiation on the ENIAC
 07/08	Bell Telephone Co. formed (predecessor of AT&T), 1877
 07/08	CDC incorporated, 1957
+07/FriLast	System Administrator Appreciation Day
 08/14	First Unix-based mallet created, 1954
 08/14	IBM PC announced, 1981
 08/22	CDC 6600 introduced, 1963
diff --git a/usr.bin/calendar/calendars/calendar.dutch b/usr.bin/calendar/calendars/calendar.dutch
index f17bafa8b9f8..ff8a5d81e184 100644
--- a/usr.bin/calendar/calendars/calendar.dutch
+++ b/usr.bin/calendar/calendars/calendar.dutch
@@ -10,7 +10,7 @@ LANG=nl_NL.ISO8859-15
  * Feestdagen
  */
 01/01	Nieuwjaar
-01/06	Drie koningen
+01/06	Driekoningen
 05/04	Dodenherdenking
 30/04	Koninginendag
 05/05	Bevrijdingsdag
@@ -31,18 +31,22 @@ LANG=nl_NL.ISO8859-15
 Easter-50	Carnival
 Easter-49	Carnival
 Easter-48	Carnival
-Easter-47	Carnival
+Easter-47	Vastenavond
 Easter-46	As woensdag
+Easter-7	Palmzondag
 Easter-3	Witte Donderdag
 Easter-2	Goede vrijdag
+Easter-1	Stille zaterdag
 Easter	Eerste paasdag
 Easter+1	Tweede paasdag
-Easter+40	Hemelvaart
+Easter+40	Hemelvaartsdag
 Easter+50	Pinksteren
 
 /*
  * Misc
  */
+05/SunSecond	Moederdag
+06/SunThird	Vaderdag
 09/TueThird	Prinsjesdag
 
 /*
@@ -50,7 +54,7 @@ Easter+50	Pinksteren
  */
 01/31	Koningin Beatrix (1938)
 04/27	Kroonprins Willem Alexander (1967)
-04/30	Prinses Juliana (RIP)
+04/30	Koningin Juliana (RIP)
 04/30	Mr. Pieter van Vollenhoven (1939)
 05/17	Prinses Maxima (1971)
 06/26	Prinses Alexia
diff --git a/usr.bin/calendar/calendars/calendar.holiday b/usr.bin/calendar/calendars/calendar.holiday
index 11dc1a998a84..6ed8be1d164f 100644
--- a/usr.bin/calendar/calendars/calendar.holiday
+++ b/usr.bin/calendar/calendars/calendar.holiday
@@ -40,7 +40,7 @@
 01/MonSecond	Adults Day in Japan
 01/MonThird	Lee-Jackson Day in Virginia (3rd Monday)
 01/MonThird	Robert E. Lee's Birthday in Alabama & Mississippi (3rd Monday)
-01/SunThird	Martin Luther King Day in New York (3rd Sunday)
+01/MonThird	Martin Luther King Day in New York (3rd Monday)
 02/01	Chinese New Year Holiday (3 days) in Taiwan
 02/02	Candlemas
 02/04	Independence Commemoration Day in Sri Lanka