diff --git a/ChangeLog b/ChangeLog
index d57ee3082e3dd3f7ad242395e28fb32014ea77d0..a564c42c66b8e93a1e048c36e8c3411480e49760 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2006-12-05  Niels M�ller  <nisse@lysator.liu.se>
+
+	* configure.ac: AC_PREREQ 2.61, for AC_PROG_MKDIR_P.
+
+	* config.make.in (datarootdir): New directory variable (for
+	autoconf-2.61).
+
 2006-11-28  Niels M�ller  <nisse@lysator.liu.se>
 
 	* configure.ac: Bumped version to 1.16.
diff --git a/config.make.in b/config.make.in
index 2bd3d3e8b0c517817bb52849d8abdbbb58f90e9a..a6fb6aa51ac66e204affda470e4b78ccec12ca61 100644
--- a/config.make.in
+++ b/config.make.in
@@ -45,6 +45,7 @@ RANLIB = @RANLIB@
 
 prefix	=	@prefix@
 exec_prefix =	@exec_prefix@
+datarootdir =	@datarootdir@
 bindir =	@bindir@
 libdir =	@libdir@
 includedir =	@includedir@
diff --git a/configure.ac b/configure.ac
index a4a04eeab998a155f9f06a716f11eea09e28edfe..badac4ed777024a5fd9b0bd36b31a3040b3af201 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,7 +3,7 @@ dnl -*- mode: shell-script; sh-indentation: 2; -*-
 dnl Process this file with autoconf to produce a configure script.
 
 AC_INIT([nettle], [1.16], [nettle-bugs@lists.lysator.liu.se])
-AC_PREREQ(2.50)
+AC_PREREQ(2.61)
 AC_CONFIG_SRCDIR([arcfour.c])
 # Needed to stop autoconf from looking for files in parent directories.
 AC_CONFIG_AUX_DIR([.])