diff --git a/ChangeLog b/ChangeLog
index 3fb1d3a69b..aa974df50e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Aug 27 14:32:31 2009  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* re.c (rb_reg_preprocess_dregexp): set encoding as ASCII-8BIT
+	  when /n is specified and the embeded string is escaped text.
+
 Thu Aug 27 13:51:12 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* random.c (random_rand): random integer can be a fixnum for
diff --git a/re.c b/re.c
index 053e673776..0cdadf537a 100644
--- a/re.c
+++ b/re.c
@@ -2285,9 +2285,11 @@ rb_reg_preprocess_dregexp(VALUE ary, int options)
 
 	src_enc = rb_enc_get(str);
 	if (options & ARG_ENCODING_NONE &&
-		src_enc != ascii8bit &&
-		rb_enc_str_coderange(str) != ENC_CODERANGE_7BIT) {
-	    rb_raise(rb_eRegexpError, "/.../n has a non escaped non ASCII character in non ASCII-8BIT script");
+		src_enc != ascii8bit) {
+	    if (rb_enc_str_coderange(str) != ENC_CODERANGE_7BIT)
+		rb_raise(rb_eRegexpError, "/.../n has a non escaped non ASCII character in non ASCII-8BIT script");
+	    else
+		src_enc = ascii8bit;
 	}
 
         StringValue(str);
diff --git a/test/ruby/test_regexp.rb b/test/ruby/test_regexp.rb
index 7631b6854d..a2911801bd 100644
--- a/test/ruby/test_regexp.rb
+++ b/test/ruby/test_regexp.rb
@@ -287,6 +287,7 @@ class TestRegexp < Test::Unit::TestCase
 
   def test_unescape
     assert_raise(ArgumentError) { s = '\\'; /#{ s }/ }
+    assert_equal(/\xFF/n, /#{ s="\\xFF" }/n)
     assert_equal(/\177/, (s = '\177'; /#{ s }/))
     assert_raise(ArgumentError) { s = '\u'; /#{ s }/ }
     assert_raise(ArgumentError) { s = '\u{ ffffffff }'; /#{ s }/ }