now hat glibc-2.6  declares futimens.
http://lists.gnu.org/archive/html/bug-gnulib/2007-05/msg00089.html

diff -ru cpio-2.7.orig/lib/utimens.c cpio-2.7/lib/utimens.c
--- cpio-2.7.orig/lib/utimens.c	2007-05-20 21:23:57.000000000 +0900
+++ cpio-2.7/lib/utimens.c	2007-05-21 08:40:22.000000000 +0900
@@ -73,7 +73,7 @@
    Return 0 on success, -1 (setting errno) on failure.  */
 
 int
-futimens (int fd ATTRIBUTE_UNUSED,
+gl_futimens (int fd ATTRIBUTE_UNUSED,
 	  char const *file, struct timespec const timespec[2])
 {
   /* There's currently no interface to set file timestamps with
@@ -166,5 +166,5 @@
 int
 utimens (char const *file, struct timespec const timespec[2])
 {
-  return futimens (-1, file, timespec);
+  return gl_futimens (-1, file, timespec);
 }
diff -ru cpio-2.7.orig/lib/utimens.h cpio-2.7/lib/utimens.h
--- cpio-2.7.orig/lib/utimens.h	2007-05-20 21:23:57.000000000 +0900
+++ cpio-2.7/lib/utimens.h	2007-05-21 08:39:57.000000000 +0900
@@ -1,3 +1,3 @@
 #include "timespec.h"
-int futimens (int, char const *, struct timespec const [2]);
+int gl_futimens (int, char const *, struct timespec const [2]);
 int utimens (char const *, struct timespec const [2]);
diff -ur tar-1.16.1.orig/src/misc.c tar-1.16.1/src/misc.c
--- tar-1.16.1.orig/src/misc.c	2007-05-21 08:57:02.000000000 +0900
+++ tar-1.16.1/src/misc.c	2007-05-21 08:57:16.000000000 +0900
@@ -518,7 +518,7 @@
     }
 #endif
 
-  return futimens (fd, file, timespec);
+  return gl_futimens (fd, file, timespec);
 }
 
 /* A description of a working directory.  */