diff -ruN ruby-1.8.3.orig/mkconfig.rb ruby-1.8.3/mkconfig.rb
--- ruby-1.8.3.orig/mkconfig.rb	2005-09-21 15:10:57.000000000 +0900
+++ ruby-1.8.3/mkconfig.rb	2005-09-21 15:17:32.000000000 +0900
@@ -74,7 +74,7 @@
 
 drive = File::PATH_SEPARATOR == ';'
 
-prefix = '/lib/ruby/' + RUBY_VERSION.sub(/\.\d+$/, '') + '/' + RUBY_PLATFORM
+prefix = '/lib64/ruby/' + RUBY_VERSION.sub(/\.\d+$/, '') + '/' + RUBY_PLATFORM
 print "  TOPDIR = File.dirname(__FILE__).chomp!(#{prefix.dump})\n"
 print "  DESTDIR = ", (drive ? "TOPDIR && TOPDIR[/\\A[a-z]:/i] || " : ""), "'' unless defined? DESTDIR\n"
 print "  CONFIG = {}\n"