diff --git a/lib/puppet/string/action.rb b/lib/puppet/string/action.rb
index ff419c090..ee3b2991b 100644
--- a/lib/puppet/string/action.rb
+++ b/lib/puppet/string/action.rb
@@ -1,89 +1,121 @@
 # -*- coding: utf-8 -*-
 require 'puppet/string'
 require 'puppet/string/option'
 
 class Puppet::String::Action
   attr_reader :name
 
   def to_s
     "#{@string}##{@name}"
   end
 
   def initialize(string, name, attrs = {})
     raise "#{name.inspect} is an invalid action name" unless name.to_s =~ /^[a-z]\w*$/
     @string  = string
     @name    = name.to_sym
     @options = {}
     attrs.each do |k, v| send("#{k}=", v) end
   end
 
   # Initially, this was defined to allow the @action.invoke pattern, which is
   # a very natural way to invoke behaviour given our introspection
   # capabilities.   Heck, our initial plan was to have the string delegate to
   # the action object for invocation and all.
   #
   # It turns out that we have a binding problem to solve: @string was bound to
   # the parent class, not the subclass instance, and we don't pass the
   # appropriate context or change the binding enough to make this work.
   #
   # We could hack around it, by either mandating that you pass the context in
   # to invoke, or try to get the binding right, but that has probably got
   # subtleties that we don't instantly think of – especially around threads.
   #
   # So, we are pulling this method for now, and will return it to life when we
   # have the time to resolve the problem.  For now, you should replace...
   #
   #     @action = @string.get_action(name)
   #     @action.invoke(arg1, arg2, arg3)
   #
   # ...with...
   #
   #     @action = @string.get_action(name)
   #     @string.send(@action.name, arg1, arg2, arg3)
   #
   # I understand that is somewhat cumbersome, but it functions as desired.
   # --daniel 2011-03-31
   #
   # PS: This code is left present, but commented, to support this chunk of
   # documentation, for the benefit of the reader.
   #
   # def invoke(*args, &block)
   #   @string.send(name, *args, &block)
   # end
 
   def invoke=(block)
+    # We need to build an instance method as a wrapper, using normal code, to
+    # be able to expose argument defaulting between the caller and definer in
+    # the Ruby API.  An extra method is, sadly, required for Ruby 1.8 to work.
+    #
+    # In future this also gives us a place to hook in additional behaviour
+    # such as calling out to the action instance to validate and coerce
+    # parameters, which avoids any exciting context switching and all.
+    #
+    # Hopefully we can improve this when we finally shuffle off the last of
+    # Ruby 1.8 support, but that looks to be a few "enterprise" release eras
+    # away, so we are pretty stuck with this for now.
+    #
+    # Patches to make this work more nicely with Ruby 1.9 using runtime
+    # version checking and all are welcome, but they can't actually help if
+    # the results are not totally hidden away in here.
+    #
+    # Incidentally, we though about vendoring evil-ruby and actually adjusting
+    # the internal C structure implementation details under the hood to make
+    # this stuff work, because it would have been cleaner.  Which gives you an
+    # idea how motivated we were to make this cleaner.  Sorry. --daniel 2011-03-31
+
+    internal_name = "#{@name} implementation, required on Ruby 1.8".to_sym
+    file = __FILE__ + "+eval"
+    line = __LINE__ + 1
+    wrapper = "def #{@name}(*args, &block)
+                 args << {} unless args.last.is_a? Hash
+                 args << block if block_given?
+                 self.__send__(#{internal_name.inspect}, *args)
+               end"
+
     if @string.is_a?(Class)
-      @string.define_method(@name, &block)
+      @string.class_eval do eval wrapper, nil, file, line end
+      @string.define_method(internal_name, &block)
     else
-      @string.meta_def(@name, &block)
+      @string.instance_eval do eval wrapper, nil, file, line end
+      @string.meta_def(internal_name, &block)
     end
   end
 
   def add_option(option)
     option.aliases.each do |name|
       if conflict = get_option(name) then
         raise ArgumentError, "Option #{option} conflicts with existing option #{conflict}"
       elsif conflict = @string.get_option(name) then
         raise ArgumentError, "Option #{option} conflicts with existing option #{conflict} on #{@string}"
       end
     end
 
     option.aliases.each do |name|
       @options[name] = option
     end
 
     option
   end
 
   def option?(name)
     @options.include? name.to_sym
   end
 
   def options
     (@options.keys + @string.options).sort
   end
 
   def get_option(name)
     @options[name.to_sym] || @string.get_option(name)
   end
 end
diff --git a/lib/puppet/string/indirector.rb b/lib/puppet/string/indirector.rb
index 0f5f405ff..48280cc77 100644
--- a/lib/puppet/string/indirector.rb
+++ b/lib/puppet/string/indirector.rb
@@ -1,86 +1,86 @@
 require 'puppet'
 require 'puppet/string'
 
 class Puppet::String::Indirector < Puppet::String
   warn "REVISIT: Need to redefine this to take arguments again, eh."
   option "--terminus TERMINUS" do
     desc "REVISIT: You can select a terminus, which has some bigger effect
 that we should describe in this file somehow."
   end
 
   def self.indirections
     Puppet::Indirector::Indirection.instances.collect { |t| t.to_s }.sort
   end
 
   def self.terminus_classes(indirection)
     Puppet::Indirector::Terminus.terminus_classes(indirection.to_sym).collect { |t| t.to_s }.sort
   end
 
   action :destroy do
     invoke { |*args| call_indirection_method(:destroy, *args) }
   end
 
   action :find do
     invoke { |*args| call_indirection_method(:find, *args) }
   end
 
   action :save do
     invoke { |*args| call_indirection_method(:save, *args) }
   end
 
   action :search do
     invoke { |*args| call_indirection_method(:search, *args) }
   end
 
   # Print the configuration for the current terminus class
   action :info do
     invoke do |*args|
       if t = indirection.terminus_class
         puts "Run mode '#{Puppet.run_mode.name}': #{t}"
       else
         $stderr.puts "No default terminus class for run mode '#{Puppet.run_mode.name}'"
       end
     end
   end
 
   attr_accessor :from
 
   def indirection_name
     @indirection_name || name.to_sym
   end
 
   # Here's your opportunity to override the indirection name.  By default
   # it will be the same name as the string.
   def set_indirection_name(name)
     @indirection_name = name
   end
 
   # Return an indirection associated with an string, if one exists
   # One usually does.
   def indirection
     unless @indirection
       @indirection = Puppet::Indirector::Indirection.instance(indirection_name)
       @indirection or raise "Could not find terminus for #{indirection_name}"
     end
     @indirection
   end
 
   def set_terminus(from)
     begin
       indirection.terminus_class = from
     rescue => detail
       raise "Could not set '#{indirection.name}' terminus to '#{from}' (#{detail}); valid terminus types are #{self.class.terminus_classes(indirection.name).join(", ") }"
     end
   end
 
   def call_indirection_method(method, *args)
     begin
-      result = indirection.send(method, *args)
+      result = indirection.__send__(method, *args)
     rescue => detail
       puts detail.backtrace if Puppet[:trace]
       raise "Could not call '#{method}' on '#{indirection_name}': #{detail}"
     end
 
     result
   end
 end