diff --git a/ChangeLog b/ChangeLog
index e8c0fc5fbb..200fffff82 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Mon Jul 19 18:34:12 2010  Tanaka Akira  <akr@fsij.org>
+
+	* ext/pathname/pathname.c (get_strpath): check the type.
+	  (path_initialize): bypass to_path call for T_STRING.
+	  (path_freeze): implemented.
+
+	* ext/pathname/lib/pathname.rb (Pathname#freeze): removed.
+
 Mon Jul 19 12:33:29 2010  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* array.c (rb_ary_clear): should not unshare embedded array, and
diff --git a/ext/pathname/lib/pathname.rb b/ext/pathname/lib/pathname.rb
index 54be13868f..56e3a4525f 100644
--- a/ext/pathname/lib/pathname.rb
+++ b/ext/pathname/lib/pathname.rb
@@ -208,7 +208,6 @@ class Pathname
 
   # :startdoc:
 
-  def freeze() super; @path.freeze; self end
   def taint() super; @path.taint; self end
   def untaint() super; @path.untaint; self end
 
diff --git a/ext/pathname/pathname.c b/ext/pathname/pathname.c
index d9917058da..cba325b0dc 100644
--- a/ext/pathname/pathname.c
+++ b/ext/pathname/pathname.c
@@ -6,7 +6,11 @@ static ID id_at_path, id_to_path;
 static VALUE
 get_strpath(VALUE obj)
 {
-    return rb_ivar_get(obj, id_at_path);
+    VALUE strpath;
+    strpath = rb_ivar_get(obj, id_at_path);
+    if (TYPE(strpath) != T_STRING)
+        rb_raise(rb_eTypeError, "unexpected @path");
+    return strpath;
 }
 
 static void
@@ -23,10 +27,15 @@ static VALUE
 path_initialize(VALUE self, VALUE arg)
 {
     VALUE str;
-    str = rb_check_funcall(arg, id_to_path, 0, NULL);
-    if (str == Qundef)
+    if (TYPE(arg) == T_STRING) {
         str = arg;
-    StringValue(str);
+    }
+    else {
+        str = rb_check_funcall(arg, id_to_path, 0, NULL);
+        if (str == Qundef)
+            str = arg;
+        StringValue(str);
+    }
     if (memchr(RSTRING_PTR(str), '\0', RSTRING_LEN(str)))
         rb_raise(rb_eArgError, "pathname contains null byte");
     str = rb_obj_dup(str);
@@ -36,6 +45,14 @@ path_initialize(VALUE self, VALUE arg)
     return self;
 }
 
+static VALUE
+path_freeze(VALUE self)
+{
+    rb_call_super(0, 0);
+    rb_str_freeze(get_strpath(self));
+    return self;
+}
+
 void
 Init_pathname()
 {
@@ -44,4 +61,5 @@ Init_pathname()
 
     rb_cPathname = rb_define_class("Pathname", rb_cObject);
     rb_define_method(rb_cPathname, "initialize", path_initialize, 1);
+    rb_define_method(rb_cPathname, "freeze", path_freeze, 0);
 }