diff --git a/ChangeLog b/ChangeLog
index 96253636a4..848d0c7058 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Jan  1 01:29:04 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* encoding.c (rb_to_encoding): raises for non-nil, non-encoding,
+	  non-string object.  [ruby-core:14634]
+
 Tue Jan  1 01:04:06 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ruby.c (process_options): rejects dummy encoding.
diff --git a/encoding.c b/encoding.c
index 6f1699e6d0..cf044b1cbe 100644
--- a/encoding.c
+++ b/encoding.c
@@ -100,9 +100,6 @@ rb_to_encoding(VALUE enc)
     if (NIL_P(enc)) return 0;
     idx = enc_check_encoding(enc);
     if (idx >= 0) return RDATA(enc)->data;
-    if (NIL_P(enc = rb_check_string_type(enc))) {
-	return 0;
-    }
     if ((idx = rb_enc_find_index(StringValueCStr(enc))) < 0) {
 	rb_raise(rb_eArgError, "unknown encoding name - %s", RSTRING_PTR(enc));
     }