diff --git a/lib/puppet/provider/package/msi.rb b/lib/puppet/provider/package/msi.rb
index c2ab37df8..86b5eacdc 100644
--- a/lib/puppet/provider/package/msi.rb
+++ b/lib/puppet/provider/package/msi.rb
@@ -1,89 +1,95 @@
 require 'puppet/provider/package'
 
 Puppet::Type.type(:package).provide(:msi, :parent => Puppet::Provider::Package) do
-  desc "Package management by installing and removing MSIs."
+  desc "Windows package management by installing and removing MSIs.
+
+    This provider requires a `source` attribute, and will accept paths to local
+    files or files on mapped drives.
+
+    This provider cannot uninstall arbitrary MSI packages; it can only uninstall
+    packages which were originally installed by Puppet."
 
   confine    :operatingsystem => :windows
   defaultfor :operatingsystem => :windows
 
   has_feature :install_options
 
   # This is just here to make sure we can find it, and fail if we
   # can't.  Unfortunately, we need to do "special" quoting of the
   # install options or msiexec.exe won't know what to do with them, if
   # the value contains a space.
   commands :msiexec => "msiexec.exe"
 
   def self.instances
     Dir.entries(installed_listing_dir).reject {|d| d == '.' or d == '..'}.collect do |name|
       new(:name => File.basename(name, '.yml'), :provider => :msi, :ensure => :installed)
     end
   end
 
   def query
     {:name => resource[:name], :ensure => :installed} if FileTest.exists?(state_file)
   end
 
   def install
     properties_for_command = nil
     if resource[:install_options]
       properties_for_command = resource[:install_options].collect do |k,v|
         property = shell_quote k
         value    = shell_quote v
 
         "#{property}=#{value}"
       end
     end
 
     # Unfortunately, we can't use the msiexec method defined earlier,
     # because of the special quoting we need to do around the MSI
     # properties to use.
     execute ['msiexec.exe', '/qn', '/norestart', '/i', shell_quote(msi_source), properties_for_command].flatten.compact.join(' ')
 
     File.open(state_file, 'w') do |f|
       metadata = {
         'name'            => resource[:name],
         'install_options' => resource[:install_options],
         'source'          => msi_source
       }
 
       f.puts(YAML.dump(metadata))
     end
   end
 
   def uninstall
     msiexec '/qn', '/norestart', '/x', msi_source
 
     File.delete state_file
   end
 
   def validate_source(value)
     fail("The source parameter cannot be empty when using the MSI provider.") if value.empty?
   end
 
   private
 
   def msi_source
     resource[:source] ||= YAML.load_file(state_file)['source'] rescue nil
 
     fail("The source parameter is required when using the MSI provider.") unless resource[:source]
 
     resource[:source]
   end
 
   def self.installed_listing_dir
     listing_dir = File.join(Puppet[:vardir], 'db', 'package', 'msi')
 
     FileUtils.mkdir_p listing_dir unless File.directory? listing_dir
 
     listing_dir
   end
 
   def state_file
     File.join(self.class.installed_listing_dir, "#{resource[:name]}.yml")
   end
 
   def shell_quote(value)
     value.include?(' ') ? %Q["#{value.gsub(/"/, '\"')}"] : value
   end
 end
diff --git a/lib/puppet/type/package.rb b/lib/puppet/type/package.rb
index 18ee85461..bfd6e4247 100644
--- a/lib/puppet/type/package.rb
+++ b/lib/puppet/type/package.rb
@@ -1,336 +1,353 @@
 # Define the different packaging systems.  Each package system is implemented
 # in a module, which then gets used to individually extend each package object.
 # This allows packages to exist on the same machine using different packaging
 # systems.
 
 module Puppet
   newtype(:package) do
     @doc = "Manage packages.  There is a basic dichotomy in package
       support right now:  Some package types (e.g., yum and apt) can
       retrieve their own package files, while others (e.g., rpm and sun)
       cannot.  For those package formats that cannot retrieve their own files,
       you can use the `source` parameter to point to the correct file.
 
       Puppet will automatically guess the packaging format that you are
       using based on the platform you are on, but you can override it
       using the `provider` parameter; each provider defines what it
       requires in order to function, and you must meet those requirements
       to use a given provider.
 
       **Autorequires:** If Puppet is managing the files specified as a
       package's `adminfile`, `responsefile`, or `source`, the package
       resource will autorequire those files."
 
     feature :installable, "The provider can install packages.",
       :methods => [:install]
     feature :uninstallable, "The provider can uninstall packages.",
       :methods => [:uninstall]
     feature :upgradeable, "The provider can upgrade to the latest version of a
         package.  This feature is used by specifying `latest` as the
         desired value for the package.",
       :methods => [:update, :latest]
     feature :purgeable, "The provider can purge packages.  This generally means
         that all traces of the package are removed, including
         existing configuration files.  This feature is thus destructive
         and should be used with the utmost care.",
       :methods => [:purge]
     feature :versionable, "The provider is capable of interrogating the
         package database for installed version(s), and can select
         which out of a set of available versions of a package to
         install if asked."
     feature :holdable, "The provider is capable of placing packages on hold
         such that they are not automatically upgraded as a result of
         other package dependencies unless explicit action is taken by
         a user or another package. Held is considered a superset of
         installed.",
       :methods => [:hold]
     feature :install_options, "The provider accepts options to be
       passed to the installer command."
 
     ensurable do
       desc <<-EOT
         What state the package should be in. On packaging systems that can
         retrieve new packages on their own, you can choose which package to
         retrieve by specifying a version number or `latest` as the ensure
         value. On packaging systems that manage configuration files separately
         from "normal" system files, you can uninstall config files by
         specifying `purged` as the ensure value.
       EOT
 
       attr_accessor :latest
 
       newvalue(:present, :event => :package_installed) do
         provider.install
       end
 
       newvalue(:absent, :event => :package_removed) do
         provider.uninstall
       end
 
       newvalue(:purged, :event => :package_purged, :required_features => :purgeable) do
         provider.purge
       end
 
       newvalue(:held, :event => :package_held, :required_features => :holdable) do
         provider.hold
       end
 
       # Alias the 'present' value.
       aliasvalue(:installed, :present)
 
       newvalue(:latest, :required_features => :upgradeable) do
         # Because yum always exits with a 0 exit code, there's a retrieve
         # in the "install" method.  So, check the current state now,
         # to compare against later.
         current = self.retrieve
         begin
           provider.update
         rescue => detail
           self.fail "Could not update: #{detail}"
         end
 
         if current == :absent
           :package_installed
         else
           :package_changed
         end
       end
 
       newvalue(/./, :required_features => :versionable) do
         begin
           provider.install
         rescue => detail
           self.fail "Could not update: #{detail}"
         end
 
         if self.retrieve == :absent
           :package_installed
         else
           :package_changed
         end
       end
 
       defaultto :installed
 
       # Override the parent method, because we've got all kinds of
       # funky definitions of 'in sync'.
       def insync?(is)
         @lateststamp ||= (Time.now.to_i - 1000)
         # Iterate across all of the should values, and see how they
         # turn out.
 
         @should.each { |should|
           case should
           when :present
             return true unless [:absent, :purged, :held].include?(is)
           when :latest
             # Short-circuit packages that are not present
             return false if is == :absent or is == :purged
 
             # Don't run 'latest' more than about every 5 minutes
             if @latest and ((Time.now.to_i - @lateststamp) / 60) < 5
               #self.debug "Skipping latest check"
             else
               begin
                 @latest = provider.latest
                 @lateststamp = Time.now.to_i
               rescue => detail
                 error = Puppet::Error.new("Could not get latest version: #{detail}")
                 error.set_backtrace(detail.backtrace)
                 raise error
               end
             end
 
             case is
             when @latest
               return true
             when :present
               # This will only happen on retarded packaging systems
               # that can't query versions.
               return true
             else
               self.debug "#{@resource.name} #{is.inspect} is installed, latest is #{@latest.inspect}"
             end
           when :absent
             return true if is == :absent or is == :purged
           when :purged
             return true if is == :purged
           # this handles version number matches and
           # supports providers that can have multiple versions installed
           when *Array(is)
             return true
           end
         }
 
         false
       end
 
       # This retrieves the current state. LAK: I think this method is unused.
       def retrieve
         provider.properties[:ensure]
       end
 
       # Provide a bit more information when logging upgrades.
       def should_to_s(newvalue = @should)
         if @latest
           @latest.to_s
         else
           super(newvalue)
         end
       end
     end
 
     newparam(:name) do
       desc "The package name.  This is the name that the packaging
       system uses internally, which is sometimes (especially on Solaris)
       a name that is basically useless to humans.  If you want to
       abstract package installation, then you can use aliases to provide
       a common name to packages:
 
           # In the 'openssl' class
           $ssl = $operatingsystem ? {
             solaris => SMCossl,
             default => openssl
           }
 
           # It is not an error to set an alias to the same value as the
           # object name.
           package { $ssl:
             ensure => installed,
             alias  => openssl
           }
 
           . etc. .
 
           $ssh = $operatingsystem ? {
             solaris => SMCossh,
             default => openssh
           }
 
           # Use the alias to specify a dependency, rather than
           # having another selector to figure it out again.
           package { $ssh:
             ensure  => installed,
             alias   => openssh,
             require => Package[openssl]
           }
 
       "
       isnamevar
     end
 
     newparam(:source) do
       desc "Where to find the actual package.  This must be a local file
         (or on a network file system) or a URL that your specific
         packaging type understands; Puppet will not retrieve files for you,
         although you can manage packages as `file` resources."
 
       validate do |value|
         provider.validate_source(value)
       end
     end
 
     newparam(:instance) do
       desc "A read-only parameter set by the package."
     end
 
     newparam(:status) do
       desc "A read-only parameter set by the package."
     end
 
     newparam(:type) do
       desc "Deprecated form of `provider`."
 
       munge do |value|
         warning "'type' is deprecated; use 'provider' instead"
         @resource[:provider] = value
 
         @resource[:provider]
       end
     end
 
     newparam(:adminfile) do
       desc "A file containing package defaults for installing packages.
         This is currently only used on Solaris.  The value will be
         validated according to system rules, which in the case of
         Solaris means that it should either be a fully qualified path
         or it should be in `/var/sadm/install/admin`."
     end
 
     newparam(:responsefile) do
       desc "A file containing any necessary answers to questions asked by
         the package.  This is currently used on Solaris and Debian.  The
         value will be validated according to system rules, but it should
         generally be a fully qualified path."
     end
 
     newparam(:configfiles) do
       desc "Whether configfiles should be kept or replaced.  Most packages
         types do not support this parameter. Defaults to `keep`."
 
       defaultto :keep
 
       newvalues(:keep, :replace)
     end
 
     newparam(:category) do
       desc "A read-only parameter set by the package."
     end
     newparam(:platform) do
       desc "A read-only parameter set by the package."
     end
     newparam(:root) do
       desc "A read-only parameter set by the package."
     end
     newparam(:vendor) do
       desc "A read-only parameter set by the package."
     end
     newparam(:description) do
       desc "A read-only parameter set by the package."
     end
 
     newparam(:allowcdrom) do
       desc "Tells apt to allow cdrom sources in the sources.list file.
         Normally apt will bail if you try this."
 
       newvalues(:true, :false)
     end
 
     newparam(:flavor) do
       desc "Newer versions of OpenBSD support 'flavors', which are
         further specifications for which type of package you want."
     end
 
     newparam(:install_options, :required_features => :install_options) do
-      desc "A hash of options to be handled by the provider when
-        installing a package."
+      desc <<-EOT
+        A hash of additional options to pass when installing a package. These
+        options are package-specific, and should be documented by the software
+        vendor. The most commonly implemented option is `INSTALLDIR`:
+
+            package { 'mysql':
+              ensure          => installed,
+              provider        => 'msi',
+              source          => 'N:/packages/mysql-5.5.16-winx64.msi',
+              install_options => { 'INSTALLDIR' => 'C:\\mysql-5.5' },
+            }
+
+        Since these options are passed verbatim to `msiexec`, any file paths
+        specified in `install_options` should use a backslash as the separator
+        character rather than a forward slash. This is the **only** place in Puppet
+        where backslash separators should be used. Note that backslashes in
+        double-quoted strings _must_ be double-escaped and backslashes
+        in single-quoted strings _may_ be double-escaped.
+      EOT
     end
 
     autorequire(:file) do
       autos = []
       [:responsefile, :adminfile].each { |param|
         if val = self[param]
           autos << val
         end
       }
 
       if source = self[:source] and absolute_path?(source)
         autos << source
       end
       autos
     end
 
     # This only exists for testing.
     def clear
       if obj = @parameters[:ensure]
         obj.latest = nil
       end
     end
 
     # The 'query' method returns a hash of info if the package
     # exists and returns nil if it does not.
     def exists?
       @provider.get(:ensure) != :absent
     end
   end
 end