diff --git a/ChangeLog b/ChangeLog
index f3ee8ad3..57953a93 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2013-08-07  Mike Frysinger  <vapier@gentoo.org>
+
+	* configure.in: Check at configure time whether libc supports
+	ruserok (support dropped by newer C libraries).
+
 2013-08-07  Nicolas François  <nicolas.francois@centraliens.net>
 
 	* man/usermod.8.xml: Fix typos and wording.
diff --git a/configure.in b/configure.in
index 29c39727..dcfffd36 100644
--- a/configure.in
+++ b/configure.in
@@ -41,7 +41,8 @@ AC_CHECK_HEADER([shadow.h],,[AC_MSG_ERROR([You need a libc with shadow.h])])
 AC_CHECK_FUNCS(l64a fchmod fchown fsync futimes getgroups gethostname getspnam \
 	gettimeofday getusershell getutent initgroups lchown lckpwdf lstat \
 	lutimes memcpy memset setgroups sigaction strchr updwtmp updwtmpx innetgr \
-	getpwnam_r getpwuid_r getgrnam_r getgrgid_r getspnam_r getaddrinfo)
+	getpwnam_r getpwuid_r getgrnam_r getgrgid_r getspnam_r getaddrinfo
+	ruserok)
 AC_SYS_LARGEFILE
 
 dnl Checks for typedefs, structures, and compiler characteristics.
@@ -194,8 +195,10 @@ AC_DEFINE_UNQUOTED(PASSWD_PROGRAM, "$shadow_cv_passwd_dir/passwd",
 
 dnl XXX - quick hack, should disappear before anyone notices :).
 AC_DEFINE(USE_SYSLOG, 1, [Define to use syslog().])
-AC_DEFINE(RLOGIN, 1, [Define if login should support the -r flag for rlogind.])
-AC_DEFINE(RUSEROK, 0, [Define to the ruserok() "success" return value (0 or 1).])
+if test "$ac_cv_func_ruserok" = "yes"; then
+	AC_DEFINE(RLOGIN, 1, [Define if login should support the -r flag for rlogind.])
+	AC_DEFINE(RUSEROK, 0, [Define to the ruserok() "success" return value (0 or 1).])
+fi
 
 AC_ARG_ENABLE(shadowgrp,
 	[AC_HELP_STRING([--enable-shadowgrp], [enable shadow group support @<:@default=yes@:>@])],