diff --git a/m4/ac_define_dir.m4 b/m4/ac_define_dir.m4
new file mode 100644
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--- /dev/null
+++ b/m4/ac_define_dir.m4
@@ -0,0 +1,34 @@
+dnl @synopsis AC_DEFINE_DIR(VARNAME, DIR [, DESCRIPTION])
+dnl
+dnl This macro sets VARNAME to the expansion of the DIR variable,
+dnl taking care of fixing up ${prefix} and such.
+dnl
+dnl VARNAME is then offered as both an output variable and a C
+dnl preprocessor symbol.
+dnl
+dnl Example:
+dnl
+dnl    AC_DEFINE_DIR([DATADIR], [datadir], [Where data are placed to.])
+dnl
+dnl @category Misc
+dnl @author Stepan Kasal <kasal@ucw.cz>
+dnl @author Andreas Schwab <schwab@suse.de>
+dnl @author Guido U. Draheim <guidod@gmx.de>
+dnl @author Alexandre Oliva
+dnl @version 2006-10-13
+dnl @license AllPermissive
+
+AC_DEFUN([AC_DEFINE_DIR], [
+  prefix_NONE=
+  exec_prefix_NONE=
+  test "x$prefix" = xNONE && prefix_NONE=yes && prefix=$ac_default_prefix
+  test "x$exec_prefix" = xNONE && exec_prefix_NONE=yes && exec_prefix=$prefix
+dnl In Autoconf 2.60, ${datadir} refers to ${datarootdir}, which in turn
+dnl refers to ${prefix}.  Thus we have to use `eval' twice.
+  eval ac_define_dir="\"[$]$2\""
+  eval ac_define_dir="\"$ac_define_dir\""
+  AC_SUBST($1, "$ac_define_dir")
+  AC_DEFINE_UNQUOTED($1, "$ac_define_dir", [$3])
+  test "$prefix_NONE" && prefix=NONE
+  test "$exec_prefix_NONE" && exec_prefix=NONE
+])