diff --git a/lib/puppet/util/tagging.rb b/lib/puppet/util/tagging.rb
index 630a17040..80e45b305 100644
--- a/lib/puppet/util/tagging.rb
+++ b/lib/puppet/util/tagging.rb
@@ -1,77 +1,78 @@
 # Created on 2008-01-19
 # Copyright Luke Kanies
 
 # A common module to handle tagging.
 #
 # So, do you want the bad news or the good news first?
 #
 # The bad news is that using an array here is hugely costly compared to using
 # a hash.  Like, the same speed empty, 50 percent slower with one item, and
 # 300 percent slower at 6 - one of our common peaks for tagging items.
 #
 # ...and that assumes an efficient implementation, just using include?.  These
 # methods have even more costs hidden in them.
 #
 # The good news is that this module has no API.  Various objects directly
 # interact with their `@tags` member as an array, or dump it directly in YAML,
 # or whatever.
 #
 # So, er, you can't actually change this.  No matter how much you want to be
 # cause it is inefficient in both CPU and object allocation terms.
 #
 # Good luck, my friend. --daniel 2012-07-17
 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 #{tag.inspect}") unless valid_tag?(tag)
       qualified << tag if tag.include?("::")
       @tags << tag unless @tags.include?(tag)
     end
 
     handle_qualified_tags( qualified )
   end
 
   # Are we tagged with the provided tag?
   def tagged?(*tags)
     not ( self.tags & tags.flatten.collect { |t| t.to_s } ).empty?
   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
 
   def tags=(tags)
     @tags = []
 
     return if tags.nil? or tags == ""
 
     tags = tags.strip.split(/\s*,\s*/) if tags.is_a?(String)
 
     tags.each {|t| tag(t) }
   end
 
   private
 
   def handle_qualified_tags(qualified)
     # LAK:NOTE See http://snurl.com/21zf8  [groups_google_com]
     x = 1
     qualified.each do |name|
       name.split("::").each do |tag|
         @tags << tag unless @tags.include?(tag)
       end
     end
   end
 
+  ValidTagRegex = /^\w[-\w:.]*$/
   def valid_tag?(tag)
-    tag =~ /^\w[-\w:.]*$/
+    tag.is_a?(String) and tag =~ ValidTagRegex
   end
 end