diff --git a/ChangeLog b/ChangeLog
index c765976b87..f75cf921f0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Tue Dec 23 08:04:58 2008  Eric Hodel  <drbrain@segment7.net>
+
+	* gem_prelude.rb: Don't remove methods twice.  [bug#555]
+
 Tue Dec 23 00:16:48 2008  Yusuke Endoh  <mame@tsg.ne.jp>
 
 	* sprintf.c (rb_str_format): fix buffer overflow.
diff --git a/gem_prelude.rb b/gem_prelude.rb
index 406f40fe5a..becf626a80 100644
--- a/gem_prelude.rb
+++ b/gem_prelude.rb
@@ -198,7 +198,13 @@ if defined?(Gem) then
 
     module QuickLoader
 
+      @loaded_full_rubygems_library = false
+
       def self.load_full_rubygems_library
+        return if @loaded_full_rubygems_library
+
+        @loaded_full_rubygems_library = true
+
         class << Gem
           Gem::GEM_PRELUDE_METHODS.each do |method_name|
             undef_method method_name