diff --git a/include/locale.h b/include/locale.h
index 8b6ad4d65c74..2477db4a3af4 100644
--- a/include/locale.h
+++ b/include/locale.h
@@ -56,6 +56,12 @@ struct lconv {
 	char	n_sep_by_space;
 	char	p_sign_posn;
 	char	n_sign_posn;
+	char	int_p_cs_precedes;
+	char	int_n_cs_precedes;
+	char	int_p_sep_by_space;
+	char	int_n_sep_by_space;
+	char	int_p_sign_posn;
+	char	int_n_sign_posn;
 };
 
 #ifndef NULL
diff --git a/lib/libc/locale/lmonetary.c b/lib/libc/locale/lmonetary.c
index 3dc6df0884a7..ad751f27ee6a 100644
--- a/lib/libc/locale/lmonetary.c
+++ b/lib/libc/locale/lmonetary.c
@@ -28,6 +28,7 @@
 __FBSDID("$FreeBSD$");
 
 #include <limits.h>
+#include <stddef.h>
 #include <stdlib.h>
 #include "lmonetary.h"
 #include "ldpart.h"
@@ -55,7 +56,13 @@ static const struct lc_monetary_T _C_monetary_locale = {
 	numempty,	/* n_cs_precedes */
 	numempty,	/* n_sep_by_space */
 	numempty,	/* p_sign_posn */
-	numempty	/* n_sign_posn */
+	numempty,	/* n_sign_posn */
+	numempty,	/* int_p_cs_precedes */
+	numempty,	/* int_n_cs_precedes */
+	numempty,	/* int_p_sep_by_space */
+	numempty,	/* int_n_sep_by_space */
+	numempty,	/* int_p_sign_posn */
+	numempty	/* int_n_sign_posn */
 };
 
 static struct lc_monetary_T _monetary_locale;
@@ -79,7 +86,9 @@ __monetary_load_locale(const char *name)
 
 	ret = __part_load_locale(name, &_monetary_using_locale,
 		_monetary_locale_buf, "LC_MONETARY",
-		LCMONETARY_SIZE, LCMONETARY_SIZE,
+		LCMONETARY_SIZE,
+		offsetof(struct lc_monetary_T, int_p_cs_precedes) /
+		    sizeof(char *),
 		(const char **)&_monetary_locale);
 	if (ret != _LDP_ERROR)
 		__mlocale_changed = 1;
@@ -98,6 +107,27 @@ __monetary_load_locale(const char *name)
 		M_ASSIGN_CHAR(n_sep_by_space);
 		M_ASSIGN_CHAR(p_sign_posn);
 		M_ASSIGN_CHAR(n_sign_posn);
+
+		/*
+		 * The six additional C99 international monetary formatting
+		 * parameters default to the national parameters when
+		 * reading FreeBSD 4 LC_MONETARY data files.
+		 */
+#define	M_ASSIGN_ICHAR(NAME)						\
+		do {							\
+			if (_monetary_locale.int_##NAME == NULL)	\
+				_monetary_locale.int_##NAME =		\
+				    _monetary_locale.NAME;		\
+			else						\
+				M_ASSIGN_CHAR(int_##NAME);		\
+		} while (0)
+
+		M_ASSIGN_ICHAR(p_cs_precedes);
+		M_ASSIGN_ICHAR(n_cs_precedes);
+		M_ASSIGN_ICHAR(p_sep_by_space);
+		M_ASSIGN_ICHAR(n_sep_by_space);
+		M_ASSIGN_ICHAR(p_sign_posn);
+		M_ASSIGN_ICHAR(n_sign_posn);
 	}
 	return (ret);
 }
diff --git a/lib/libc/locale/lmonetary.h b/lib/libc/locale/lmonetary.h
index d32689793922..45ec3235b578 100644
--- a/lib/libc/locale/lmonetary.h
+++ b/lib/libc/locale/lmonetary.h
@@ -45,6 +45,12 @@ struct lc_monetary_T {
 	const char	*n_sep_by_space;
 	const char	*p_sign_posn;
 	const char	*n_sign_posn;
+	const char	*int_p_cs_precedes;
+	const char	*int_n_cs_precedes;
+	const char	*int_p_sep_by_space;
+	const char	*int_n_sep_by_space;
+	const char	*int_p_sign_posn;
+	const char	*int_n_sign_posn;
 };
 
 struct lc_monetary_T *__get_current_monetary_locale(void);
diff --git a/lib/libc/locale/localeconv.c b/lib/libc/locale/localeconv.c
index 804e9fdad08e..d10ba1f97427 100644
--- a/lib/libc/locale/localeconv.c
+++ b/lib/libc/locale/localeconv.c
@@ -85,6 +85,12 @@ localeconv()
 	M_ASSIGN_CHAR(n_sep_by_space);
 	M_ASSIGN_CHAR(p_sign_posn);
 	M_ASSIGN_CHAR(n_sign_posn);
+	M_ASSIGN_CHAR(int_p_cs_precedes);
+	M_ASSIGN_CHAR(int_n_cs_precedes);
+	M_ASSIGN_CHAR(int_p_sep_by_space);
+	M_ASSIGN_CHAR(int_n_sep_by_space);
+	M_ASSIGN_CHAR(int_p_sign_posn);
+	M_ASSIGN_CHAR(int_n_sign_posn);
 	__mlocale_changed = 0;
     }
 
diff --git a/lib/libc/locale/setlocale.3 b/lib/libc/locale/setlocale.3
index a1bb367bd7b1..75808672a823 100644
--- a/lib/libc/locale/setlocale.3
+++ b/lib/libc/locale/setlocale.3
@@ -35,7 +35,7 @@
 .\"	@(#)setlocale.3	8.1 (Berkeley) 6/9/93
 .\" $FreeBSD$
 .\"
-.Dd June 9, 1993
+.Dd October 5, 2002
 .Dt SETLOCALE 3
 .Os
 .Sh NAME
@@ -163,6 +163,12 @@ struct lconv {
 	char	n_sep_by_space;
 	char	p_sign_posn;
 	char	n_sign_posn;
+	char	int_p_cs_precedes;
+	char	int_n_cs_precedes;
+	char	int_p_sep_by_space;
+	char	int_n_sep_by_space;
+	char	int_p_sign_posn;
+	char	int_n_sign_posn;
 };
 .Ed
 .Pp
@@ -249,6 +255,30 @@ Just after
 Like
 .Fa p_sign_posn
 but for negative currency values.
+.It Fa int_p_cs_precedes
+Same as
+.Fa p_cs_precedes ,
+but for internationally formatted monetary quantities.
+.It Fa int_n_cs_precedes
+Same as
+.Fa n_cs_precedes ,
+but for internationally formatted monetary quantities.
+.It Fa int_p_sep_by_space
+Same as
+.Fa p_sep_by_space ,
+but for internationally formatted monetary quantities.
+.It Fa int_n_sep_by_space
+Same as
+.Fa n_sep_by_space ,
+but for internationally formatted monetary quantities.
+.It Fa int_p_sign_posn
+Same as
+.Fa p_sign_posn ,
+but for internationally formatted monetary quantities.
+.It Fa int_n_sign_posn
+Same as
+.Fa n_sign_posn ,
+but for internationally formatted monetary quantities.
 .El
 .Pp
 Unless mentioned above,
@@ -311,7 +341,7 @@ The
 and
 .Fn localeconv
 functions conform to
-.St -isoC .
+.St -isoC-99 .
 .Sh HISTORY
 The
 .Fn setlocale