diff --git a/ext/patron/session_ext.c b/ext/patron/session_ext.c
index 3063aea..1cbe0ca 100644
--- a/ext/patron/session_ext.c
+++ b/ext/patron/session_ext.c
@@ -966,11 +966,11 @@ void Init_session_ext() {
   rb_define_singleton_method(cSession, "unescape",   session_unescape,         1);
   rb_define_method(cSession, "unescape",       session_unescape,       1);
 
-  rb_define_method(cSession, "handle_request", session_handle_request, 1);
+  rb_define_private_method(cSession, "handle_request", session_handle_request, 1);
   rb_define_method(cSession, "reset",          session_interrupt,      0);
   rb_define_method(cSession, "interrupt",      session_interrupt,      0);
-  rb_define_method(cSession, "add_cookie_file", add_cookie_file, 1);
-  rb_define_method(cSession, "set_debug_file", set_debug_file, 1);
+  rb_define_private_method(cSession, "add_cookie_file", add_cookie_file, 1);
+  rb_define_private_method(cSession, "set_debug_file", set_debug_file, 1);
   rb_define_alias(cSession, "urlencode", "escape");
   rb_define_alias(cSession, "urldecode", "unescape");
 
diff --git a/lib/patron/session.rb b/lib/patron/session.rb
index bcdaf9e..c7d9649 100644
--- a/lib/patron/session.rb
+++ b/lib/patron/session.rb
@@ -103,8 +103,6 @@ class Session
     # @see low_speed_time
     attr_accessor :low_speed_limit
 
-    private :handle_request, :add_cookie_file, :set_debug_file
-
     # @return [#call, nil] callable object that will be called with 4 arguments
     #    during request/response execution - `dltotal`, `dlnow`, `ultotal`, `ulnow`.
     #    All these arguments are in bytes.