Index: configure.in
===================================================================
--- configure.in	(revision 23726)
+++ configure.in	(working copy)
@@ -2309,7 +2309,7 @@
 AC_SUBST(rubylibprefix)
 
 RI_BASE_NAME=`echo ${RUBY_BASE_NAME} | sed 's/ruby/ri/'`
-ridir='${DATAROOTDIR}/${RI_BASE_NAME}'
+ridir="${datarootdir}/${RI_BASE_NAME}"
 AC_ARG_WITH(ridir,
 	    AS_HELP_STRING([--with-ridir=DIR], [ri documentation [[DATAROOTDIR/ri]]]),
 	    [ridir=$withval])