diff --git a/rubygems/ChangeLog b/rubygems/ChangeLog
index bed83bc9..a9294349 100644
--- a/rubygems/ChangeLog
+++ b/rubygems/ChangeLog
@@ -1,3 +1,8 @@
+2004-06-08  Gavin Sinclair <gsinclair@soyabean.com.au>
+	* lib/rubygems/installer.rb: don't warn about not being able to
+	  install a library stub if a library stub is already installed.
+	  Still warn if it's not a library stub that's there already.
+
 2004-06-08  Gavin Sinclair <gsinclair@soyabean.com.au>
 	* bin/gem: renamed --upgrade-dist to --upgrade--all and fixed bug.
 	* lib/rubygems/installer.rb: fixed bug with Ruby version assertion.
diff --git a/rubygems/lib/rubygems/installer.rb b/rubygems/lib/rubygems/installer.rb
index 16eae373..a9507666 100644
--- a/rubygems/lib/rubygems/installer.rb
+++ b/rubygems/lib/rubygems/installer.rb
@@ -159,10 +159,12 @@ def generate_library_stubs(spec)
         sitelibdir = Config::CONFIG['sitelibdir']
         if FileTest.writable?(sitelibdir)
           target_file = File.join(sitelibdir, "#{spec.autorequire}.rb")
-          if FileTest.exist?(target_file) 
-            STDERR.puts "(WARN) Library file '#{target_file}'"
-            STDERR.puts "       already exists; not overwriting.  If you want to force a"
-            STDERR.puts "       library stub, delete the file and reinstall."
+          if FileTest.exist?(target_file)
+            unless library_stub?(target_file)
+              STDERR.puts "(WARN) Library file '#{target_file}'"
+              STDERR.puts "       already exists; not overwriting.  If you want to force a"
+              STDERR.puts "       library stub, delete the file and reinstall."
+            end
           else
             # Create #{autorequire}.rb in #{target_dir}.
           unless File.exist? File.dirname(target_file)
@@ -199,6 +201,17 @@ def library_stub_text(name, file_name)
 TEXT
       text
     end
+
+    ##
+    # Returns true iff the given filename contains a library stub.  (Best guess!)
+    #
+    def library_stub?(filename)
+      lines = File.read(filename)
+      lines.grep(/^# This file was generated by RubyGems/) and
+        lines.grep(/is installed as part of a gem, and/) and
+        lines.grep(/^#/).size == 7 and
+        lines.size == 11
+    end
     
     def build_extensions(directory, spec)
       return unless spec.extensions.size > 0