--- BUILD/ruby-1.9.1-p378/configure.in.old	2010-01-17 07:20:12.000000000 +0100
+++ BUILD/ruby-1.9.1-p378/configure.in	2010-01-17 07:20:12.000000000 +0100
@@ -2111,6 +2111,14 @@
 AC_SUBST(sitehdrdir)dnl
 AC_SUBST(vendorhdrdir)dnl
 
+AC_ARG_WITH(old-os,
+		[  --with-old-os=OS specify the os to add into search path],
+		[old_os=$withval])
+if test "$old_os" != ""; then
+    AC_DEFINE_UNQUOTED(RUBY_OLD_ARCHLIB, "${RUBY_LIB_PATH}/${target_cpu}-${old_os}")
+    AC_DEFINE_UNQUOTED(RUBY_OLD_SITE_ARCHLIB, "${RUBY_SITE_LIB_PATH2}/${target_cpu}-${old_os}")
+fi
+
 AC_ARG_WITH(mantype,
 		[  --with-mantype=TYPE specify man page type; TYPE is one of man and doc],
 		[
--- BUILD/ruby-1.9.1-p378/ruby.c.old	2009-08-08 17:34:48.000000000 +0200
+++ BUILD/ruby-1.9.1-p378/ruby.c	2010-01-17 07:20:12.000000000 +0100
@@ -412,6 +412,9 @@
     incpush(RUBY_RELATIVE(RUBY_SITE_THIN_ARCHLIB));
 #endif
     incpush(RUBY_RELATIVE(RUBY_SITE_ARCHLIB));
+#ifdef RUBY_OLD_SITE_ARCHLIB
+    incpush(RUBY_RELATIVE(RUBY_OLD_SITE_ARCHLIB));
+#endif
     incpush(RUBY_RELATIVE(RUBY_SITE_LIB));
 
     incpush(RUBY_RELATIVE(RUBY_VENDOR_LIB2));
@@ -426,6 +429,9 @@
     incpush(RUBY_RELATIVE(RUBY_THIN_ARCHLIB));
 #endif
     incpush(RUBY_RELATIVE(RUBY_ARCHLIB));
+#ifdef RUBY_OLD_ARCHLIB
+    incpush(RUBY_RELATIVE(RUBY_OLD_ARCHLIB));
+#endif
 
     if (safe_level == 0) {
 	incpush(".");