diff --git a/ChangeLog b/ChangeLog
index 122f3758b8..a527e7bf2d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Jun 16 07:14:48 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/stringio/stringio.c (strio_readline, strio_each)
+	  (strio_readlines): set lastline.  [ruby-core:17257]
+
 Mon Jun 16 01:49:39 2008  Koichi Sasada  <ko1@atdot.net>
 
 	* eval.c (rb_f_block_given_p): fix to skip class frame.
diff --git a/ext/stringio/stringio.c b/ext/stringio/stringio.c
index 8b5abb3f62..d140ced7e7 100644
--- a/ext/stringio/stringio.c
+++ b/ext/stringio/stringio.c
@@ -928,7 +928,7 @@ strio_gets(int argc, VALUE *argv, VALUE self)
 static VALUE
 strio_readline(int argc, VALUE *argv, VALUE self)
 {
-    VALUE line = strio_getline(argc, argv, readable(StringIO(self)));
+    VALUE line = strio_gets(argc, argv, self);
     if (NIL_P(line)) rb_eof_error();
     return line;
 }
@@ -953,6 +953,7 @@ strio_each(int argc, VALUE *argv, VALUE self)
     RETURN_ENUMERATOR(self, argc, argv);
 
     while (!NIL_P(line = strio_getline(argc, argv, readable(ptr)))) {
+	rb_lastline_set(line);
 	rb_yield(line);
     }
     return self;
@@ -974,6 +975,7 @@ strio_readlines(int argc, VALUE *argv, VALUE self)
     while (!NIL_P(line = strio_getline(argc, argv, readable(ptr)))) {
 	rb_ary_push(ary, line);
     }
+    rb_lastline_set(Qnil);
     return ary;
 }