diff --git a/lib/puppet/util/tagging.rb b/lib/puppet/util/tagging.rb
index 9abb3fb2b..8a50f3458 100644
--- a/lib/puppet/util/tagging.rb
+++ b/lib/puppet/util/tagging.rb
@@ -1,39 +1,39 @@
 # Created on 2008-01-19
 # Copyright Luke Kanies
 
 # A common module to handle tagging.
 module Puppet::Util::Tagging
     # Add a tag to our current list.  These tags will be added to all
     # of the objects contained in this scope.
     def tag(*ary)
         @tags ||= []
 
         qualified = []
 
         ary.collect { |tag| tag.to_s.downcase }.each do |tag|
             fail(Puppet::ParseError, "Invalid tag %s" % tag.inspect) unless valid_tag?(tag)
             qualified << tag if tag.include?("::")
             @tags << tag unless @tags.include?(tag)
         end
 
         qualified.collect { |name| name.split("::") }.flatten.each { |tag| @tags << tag unless @tags.include?(tag) }
     end
 
     # Are we tagged with the provided tag?
     def tagged?(tag)
         defined?(@tags) and @tags.include?(tag.to_s)
     end
 
     # Return a copy of the tag list, so someone can't ask for our tags
     # and then modify them.
     def tags
         @tags ||= []
         @tags.dup
     end
 
     private
 
     def valid_tag?(tag)
-        tag =~ /^\w[-\w:]*$/
+        tag =~ /^\w[-\w:.]*$/
     end
 end
diff --git a/spec/unit/util/tagging.rb b/spec/unit/util/tagging.rb
index 91cbb213d..d61ee8ccb 100755
--- a/spec/unit/util/tagging.rb
+++ b/spec/unit/util/tagging.rb
@@ -1,88 +1,92 @@
 #!/usr/bin/env ruby
 #
 #  Created by Luke Kanies on 2008-01-19.
 #  Copyright (c) 2007. All rights reserved.
 
 require File.dirname(__FILE__) + '/../../spec_helper'
 
 require 'puppet/util/tagging'
 
 describe Puppet::Util::Tagging, "when adding tags" do
     before do
         @tagger = Object.new
         @tagger.extend(Puppet::Util::Tagging)
     end
 
     it "should have a method for adding tags" do
         @tagger.should be_respond_to(:tag)
     end
 
     it "should have a method for returning all tags" do
         @tagger.should be_respond_to(:tags)
     end
 
     it "should add tags to the returned tag list" do
         @tagger.tag("one")
         @tagger.tags.should be_include("one")
     end
 
     it "should not add duplicate tags to the returned tag list" do
         @tagger.tag("one")
         @tagger.tag("one")
         @tagger.tags.should == ["one"]
     end
 
     it "should return a duplicate of the tag list, rather than the original" do
         @tagger.tag("one")
         tags = @tagger.tags
         tags << "two"
         @tagger.tags.should_not be_include("two")
     end
 
     it "should add all provided tags to the tag list" do
         @tagger.tag("one", "two")
         @tagger.tags.should be_include("one")
         @tagger.tags.should be_include("two")
     end
 
     it "should fail on tags containing '*' characters" do
         lambda { @tagger.tag("bad*tag") }.should raise_error(Puppet::ParseError)
     end
 
     it "should fail on tags starting with '-' characters" do
         lambda { @tagger.tag("-badtag") }.should raise_error(Puppet::ParseError)
     end
 
     it "should fail on tags containing ' ' characters" do
         lambda { @tagger.tag("bad tag") }.should raise_error(Puppet::ParseError)
     end
 
     it "should allow alpha tags" do
         lambda { @tagger.tag("good_tag") }.should_not raise_error(Puppet::ParseError)
     end
 
+    it "should allow tags containing '.' characters" do
+        lambda { @tagger.tag("good.tag") }.should_not raise_error(Puppet::ParseError)
+    end
+
     it "should provide a method for testing tag validity" do
         @tagger.metaclass.publicize_methods(:valid_tag?)  { @tagger.should be_respond_to(:valid_tag?) }
     end
 
     it "should add qualified classes as tags" do
         @tagger.tag("one::two")
         @tagger.tags.should be_include("one::two")
     end
 
     it "should add each part of qualified classes as tags" do
         @tagger.tag("one::two::three")
         @tagger.tags.should be_include("one")
         @tagger.tags.should be_include("two")
         @tagger.tags.should be_include("three")
     end
 
     it "should indicate when the object is tagged with a provided tag" do
         @tagger.tag("one")
         @tagger.should be_tagged("one")
     end
 
     it "should indicate when the object is not tagged with a provided tag" do
         @tagger.should_not be_tagged("one")
     end
 end