diff --git a/man7/feature_test_macros.7 b/man7/feature_test_macros.7
index 24131e2f7..91ac5f150 100644
--- a/man7/feature_test_macros.7
+++ b/man7/feature_test_macros.7
@@ -22,7 +22,7 @@
 .\" Formatted or processed versions of this manual, if unaccompanied by
 .\" the source, must acknowledge the copyright and authors of this work.
 .\"
-.TH FEATURE_TEST_MACROS 7 2010-09-10 "Linux" "Linux Programmer's Manual"
+.TH FEATURE_TEST_MACROS 7 2011-09-17 "Linux" "Linux Programmer's Manual"
 .SH NAME
 feature_test_macros \- feature test macros
 .SH SYNOPSIS
@@ -196,6 +196,16 @@ This macro is also implicitly defined if
 .B _XOPEN_SOURCE
 is defined with a value of 500 or more.
 .TP
+.B _ISOC95_SOURCE
+Exposes ISO C (1990) Amendment 1 definitions (also known as C95).
+This macro is recognized since glibc 2.12.
+The primary change in C95 was support for international character sets.
+The C95 changes were included in the subsequent C99 standard
+(in other words,
+.B _ISOC99_SOURCE
+implies
+.BR _ISOC95_SOURCE ).
+.TP
 .B _ISOC99_SOURCE
 Exposes C99 extensions to ISO C (1990).
 This macro is recognized since glibc 2.1.3;