diff --git a/man3/isalpha.3 b/man3/isalpha.3
index ca441da28..9fc5b6f67 100644
--- a/man3/isalpha.3
+++ b/man3/isalpha.3
@@ -27,7 +27,7 @@
 .\" Modified Sat Sep  2 21:52:01 1995 by Jim Van Zandt <jrv@vanzandt.mv.com>
 .\" Modified Mon May 27 22:55:26 1996 by Martin Schulze (joey@linux.de)
 .\"
-.TH ISALPHA 3 2010-09-20 "GNU" "Linux Programmer's Manual"
+.TH ISALPHA 3 2014-01-27 "GNU" "Linux Programmer's Manual"
 .SH NAME
 isalnum, isalpha, isascii, isblank, iscntrl, isdigit, isgraph, islower,
 isprint, ispunct, isspace, isupper, isxdigit \- character
@@ -162,6 +162,24 @@ The values returned are nonzero if the character
 .I c
 falls into the tested class, and a zero value
 if not.
+.SH ATTRIBUTES
+.SS Multithreading (see pthreads(7))
+The
+.BR isalnum (),
+.BR isalpha (),
+.BR isascii (),
+.BR isblank (),
+.BR iscntrl (),
+.BR isdigit (),
+.BR isgraph (),
+.BR islower (),
+.BR isprint (),
+.BR ispunct (),
+.BR isspace (),
+.BR isupper (),
+and
+.BR isxdigit ()
+functions are thread-safe.
 .SH CONFORMING TO
 C99, 4.3BSD.
 C89 specifies all of these functions except