diff --git a/ChangeLog b/ChangeLog
index 1e3731f763..24e9ddf42c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Apr 21 17:01:44 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* iseq.c (rb_iseq_compile_with_option): check if src is a strring.
+	  [ruby-core:16453]
+
 Mon Apr 21 16:06:47 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* enumerator.c (enumerator_init): preserve the method name in ID.
diff --git a/iseq.c b/iseq.c
index c54239a81d..f475ca7a37 100644
--- a/iseq.c
+++ b/iseq.c
@@ -438,7 +438,7 @@ VALUE
 rb_iseq_compile_with_option(VALUE src, VALUE file, VALUE line, VALUE opt)
 {
     rb_compile_option_t option;
-    NODE *node = compile_string(src, file, line);
+    NODE *node = compile_string(StringValue(src), file, line);
     rb_thread_t *th = GET_THREAD();
     make_compile_option(&option, opt);