diff -ur ruby-1.8.4/lib/cgi.rb ruby-1.8.4-xhtml_cgi/lib/cgi.rb
--- ruby-1.8.4/lib/cgi.rb	2005-10-06 21:01:22.000000000 -0400
+++ ruby-1.8.4-xhtml_cgi/lib/cgi.rb	2006-01-20 13:38:26.000000000 -0500
@@ -266,10 +266,13 @@
 #   end
 # 
 #   # add HTML generation methods
-#   CGI.new("html3")    # html3.2
-#   CGI.new("html4")    # html4.01 (Strict)
-#   CGI.new("html4Tr")  # html4.01 Transitional
-#   CGI.new("html4Fr")  # html4.01 Frameset
+#   CGI.new("html3")      # html3.2
+#   CGI.new("html4")      # html4.01 (Strict)
+#   CGI.new("html4Tr")    # html4.01 Transitional
+#   CGI.new("html4Fr")    # html4.01 Frameset
+#   CGI.new("xhtml10")    # XHTML 1.0 (Strict)
+#   CGI.new("xhtml10Tr")  # XHTML 1.0 Transitional
+#   CGI.new("xhtml10Fr")  # XHTML 1.0 Frameset
 #
 class CGI
 
@@ -536,6 +539,24 @@
   # 
   # This method does not perform charset conversion. 
   #
+  # Content-Type and XHTML 1.0 Output:
+  #
+  # In accordance with the oft-heralded Principle of Least Suprise and
+  # both backwards and browser compatability, the Content-Type for
+  # generated XHTML defaults to 'text/html'.  However, if you're
+  # generating XHTML 1.0 content (i.e., you've created a CGI with the
+  # xhtml10, xhtml10Tr, or xhtml10Fr HTML output types), for user agents
+  # which are XHTML-aware, you might consider using a more
+  # XHTML-friendly content type. such as 'application/xhtml+xml',
+  # 'application/xml', or 'text/xml'.  In particular, the use of
+  # 'application/xhtml+xml' change the default character encoding
+  # behavior, rendering, and validation that user agents make about your
+  # document.  The nuances of these character types and the effect they
+  # have on conforming user agents are covered in gory detail in the W3C
+  # note "XHTML Media Types" at the following URL:
+  #
+  #   http://www.w3.org/TR/xhtml-media-types/
+  #
   def header(options = "text/html")
 
     buf = ""
@@ -1224,35 +1245,83 @@
   # Provides methods for code generation for tags following
   # the various DTD element types.
   module TagMaker # :nodoc:
+    TagStyle = Struct.new(
+      # upper-case element and attribute names on output 
+      # (true for HTML, false for XHTML)
+      :upcase,  
+
+      # allow bare (minimized) attributes (attributes without values)
+      # (true for HTML, false for XHTML)
+      :bare_attrs, 
+
+      # always close elements, even if empty
+      # (false for HTML, true for XHTML)
+      :always_close, 
+
+      # add implicit IDs to elements with name attributes but not IDs
+      # (false for HTML, true for XHTML10)
+      :implicit_ids
+    )
+
+    # HTML3/4 tag style
+    # this is declared here because it's the default tag style if
+    # unspecified in the methods below (to preserve
+    # backwards-compatability for other extensions depending on these
+    # methods)
+    HTML_TAG_STYLE = TagMaker::TagStyle.new(true, true, false, false)
+    XHTML10_TAG_STYLE = TagMaker::TagStyle.new(false, false, true, true)
+
 
     # Generate code for an element with required start and end tags.
     #
     #   - -
-    def nn_element_def(element)
-      nOE_element_def(element, <<-END)
+    def nn_element_def(element, style = HTML_TAG_STYLE)
+      elem_name = style.upcase ? element.upcase : element
+      nOE_element_def(element, <<-END, style)
           if block_given?
             yield.to_s
           else
             ""
           end +
-          "</#{element.upcase}>"
+          "</#{elem_name}>"
       END
     end
 
     # Generate code for an empty element.
     #
     #   - O EMPTY
-    def nOE_element_def(element, append = nil)
+    def nOE_element_def(element, append = nil, style = HTML_TAG_STYLE, close_elem = false)
+      elem_name = style.upcase ? element.upcase : element
+      elem_end = (close_elem && style.always_close) ? ' />' : '>'
+      attr_name = style.upcase ? 'name' : 'name.downcase'
+
       s = <<-END
-          "<#{element.upcase}" + attributes.collect{|name, value|
+          has_id = #{style.implicit_ids}
+          has_id &&= attributes.keys.map { |v| v.downcase}.include?('id')
+
+          "<#{elem_name}" + attributes.collect{|name, value|
             next unless value
-            " " + CGI::escapeHTML(name) +
+            " " + CGI::escapeHTML(#{attr_name}) +
             if true == value
-              ""
+              #{style.bare_attrs} ? "" : '="' + CGI::escapeHTML(#{attr_name}) + '"'
             else
-              '="' + CGI::escapeHTML(value) + '"'
+              val = '="' + CGI::escapeHTML(value) + '"'
+
+              # what we're doing here is cloning the name attribute to
+              # an ID attribute if the implicit_ids style flag is set
+              # and an ID attribute wasn't explicitly specified.  this
+              # is necessary to maintain backwards compatability with
+              # the existing CGI modules and forwards compatability with
+              # XHTML 1.0 and (eventually) XHTML 1.1.  This approach has
+              # the added bonus of being guaranteed to work in older
+              # user agents.
+              val += ' id' + val if #{style.implicit_ids} && 
+                                    !has_id && 'name' == name.downcase
+
+              # return attribute value assignment
+              val
             end
-          }.to_s + ">"
+          }.to_s + "#{elem_end}"
       END
       s.sub!(/\Z/, " +") << append if append
       s
@@ -1262,10 +1331,11 @@
     # start) tag is optional.
     #
     #   O O or - O
-    def nO_element_def(element)
-      nOE_element_def(element, <<-END)
+    def nO_element_def(element, style = HTML_TAG_STYLE)
+      elem_name = style.upcase ? element.upcase : element
+      nOE_element_def(element, <<-END, style)
           if block_given?
-            yield.to_s + "</#{element.upcase}>"
+            yield.to_s + "</#{elem_name}>"
           else
             ""
           end
@@ -1554,7 +1624,7 @@
       end
       if @output_hidden
         body += @output_hidden.collect{|k,v|
-          "<INPUT TYPE=\"HIDDEN\" NAME=\"#{k}\" VALUE=\"#{v}\">"
+          hidden(k, v)
         }.to_s
       end
       super(attributes){body}
@@ -1594,6 +1664,14 @@
     # "DOCTYPE", if given, is used as the leading DOCTYPE SGML tag; it
     # should include the entire text of this tag, including angle brackets.
     #
+    # For XHTML 1.0 output, two addition pseudo-attributes, "XMLDECL"
+    # and "XML_ENCODING", are available.  "XMLDECL" is, as the name
+    # implies, the full XML declaration for the output document, and, 
+    # like the "DOCTYPE" pseudo-element, should include the entire text
+    # of the tag, including angle brackets. "XML_ENCODING" is the top-
+    # level XML encoding for the document, and defaults to "UTF-8" if
+    # unspecified.
+    #
     # The body of the html element is supplied as a block.
     # 
     #   html{ "string" }
@@ -1647,6 +1725,39 @@
         buf += doctype
       end
 
+      # if the method xmldecl exists, then print out an XML
+      # declaration.  IE doesn't render in strict mode if the first
+      # element in the document isn't a DOCTYPE declaration, so we need
+      # to put the XML declaration after the DOCTYPE declaration, even
+      # though it really makes more sense the other way around.
+      if respond_to?(:xmldecl)
+        buf += if attributes.key?('XMLDECL')
+          # if the pseudo-attribute XMLDECL is specified, then delete it
+          # from the attribute list and use that instead of the
+          # pre-defined XML declaration
+          attributes.delete('XMLDECL')
+        else
+          # if the pseudo-attribute XML_ENCODING is specified, then
+          # delete it from the attribute list and use it instead of
+          # UTF-8
+          encoding = if attributes.key?('XMLENCODING') 
+            attributes.delete('XML_ENCODING')
+          else
+            'UTF-8'
+          end
+
+          # render the XML declaration with the specified encoding
+          xmldecl(encoding)
+        end
+      end
+      
+
+      # add the xml namespace unless the xmlns method isn't defined
+      # _and_ we don't have the xmlns attribute set
+      unless attributes.key?('xmlns') || !respond_to?(:xmlns)
+        attributes['xmlns'] = xmlns
+      end
+
       if block_given?
         buf += super(attributes){ yield }
       else
@@ -2055,7 +2166,6 @@
 
   # Mixin module for HTML version 3 generation methods.
   module Html3 # :nodoc:
-
     # The DOCTYPE declaration for this version of HTML
     def doctype
       %|<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">|
@@ -2236,6 +2346,154 @@
 
   end # Html4Fr
 
+  # Mixin module for generating XHTML version 1.0
+  module Xhtml10 # :nodoc:
+
+    # The DOCTYPE declaration for this version of HTML
+    def doctype
+      %|<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">|
+    end
+
+    def xmldecl(enc = 'UTF-8')
+      %|<?xml version='1.0' encoding='#{enc}'?>|
+    end
+
+    def xmlns
+      'http://www.w3.org/1999/xhtml'
+    end
+
+    # Initialise the HTML generation methods for this version.
+    def element_init
+      style = TagMaker::XHTML10_TAG_STYLE
+
+      extend TagMaker
+      methods = ""
+      # - -
+      for element in %w[tt i b big small em strong dfn code samp kbd
+        var cite abbr acronym sub sup span bdo address div map object
+        h1 h2 h3 h4 h5 h6 pre q ins del dl ol ul label select optgroup
+        fieldset legend button table title style script noscript
+        textarea form a blockquote caption 
+        html body p dt dd li option theadtfood tbody colgroup tr th td head ]
+        methods += <<-BEGIN + nn_element_def(element, style) + <<-END
+          def #{element}(attributes = {})
+        BEGIN
+          end
+        END
+      end
+
+      # - O EMPTY
+      for element in %w[img base br area link param hr input col meta ]
+        methods += <<-BEGIN + nOE_element_def(element, nil, style, true) + <<-END
+          def #{element}(attributes = {})
+        BEGIN
+          end
+        END
+      end
+
+      eval(methods)
+    end
+
+  end # Xhtml10
+
+
+  # Mixin module for HTML version 4 transitional generation methods.
+  module Xhtml10Tr # :nodoc:
+
+    # The DOCTYPE declaration for this version of HTML
+    def doctype
+      %|<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">|
+    end
+
+    def xmldecl(enc = 'UTF-8')
+      %|<?xml version='1.0' encoding='#{enc}'?>|
+    end
+
+    def xmlns
+      'http://www.w3.org/1999/xhtml'
+    end
+
+    # Initialise the HTML generation methods for this version.
+    def element_init
+      style = TagMaker::XHTML10_TAG_STYLE
+
+      extend TagMaker
+      methods = ""
+      # - -
+      for element in %w[ tt i b u s strike big small em strong dfn
+          code samp kbd var cite abbr acronym font sub sup span bdo
+          address div center map object applet h1 h2 h3 h4 h5 h6 pre q
+          ins del dl ol ul dir menu label select optgroup fieldset
+          legend button table iframe noframes title style script
+          noscript textarea form a blockquote caption html body p dt dd
+          li option thead tfoot tbody colgroup tr th td head]
+        methods += <<-BEGIN + nn_element_def(element, style) + <<-END
+          def #{element}(attributes = {})
+        BEGIN
+          end
+        END
+      end
+
+      # - O EMPTY
+      for element in %w[ img base basefont br area link param hr input
+          col isindex meta ]
+        methods += <<-BEGIN + nOE_element_def(element, nil, style, true) + <<-END
+          def #{element}(attributes = {})
+        BEGIN
+          end
+        END
+      end
+
+      eval(methods)
+    end
+
+  end # Xhtml10Tr
+  
+  # Mixin module for generating XHTML version 1.0 with framesets.
+  module Xhtml4Fr # :nodoc:
+
+    # The DOCTYPE declaration for this version of HTML
+    def doctype
+      %|<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">|
+    end
+
+    # the XML declaration for this XHTML document
+    def xmldecl(enc = 'UTF-8')
+      %|<?xml version='1.0' encoding='#{enc}'?>|
+    end
+
+    # the XML namespace attribute for this XHTML document
+    def xmlns
+      'http://www.w3.org/1999/xhtml'
+    end
+
+    # Initialise the HTML generation methods for this version.
+    def element_init
+      style = TagMaker::XHTML10_TAG_STYLE
+
+      methods = ""
+      # - -
+      for element in %w[ frameset ]
+        methods += <<-BEGIN + nn_element_def(element, style) + <<-END
+          def #{element}(attributes = {})
+        BEGIN
+          end
+        END
+      end
+
+      # - O EMPTY
+      for element in %w[ frame ]
+        methods += <<-BEGIN + nOE_element_def(element, nil, style, true) + <<-END
+          def #{element}(attributes = {})
+        BEGIN
+          end
+        END
+      end
+      eval(methods)
+    end
+
+  end # Xhtml10Fr
+
 
   # Creates a new CGI instance.
   #
@@ -2246,6 +2504,9 @@
   # html4:: HTML 4.0
   # html4Tr:: HTML 4.0 Transitional
   # html4Fr:: HTML 4.0 with Framesets
+  # xhtml10:: XHTML 1.0 (Strict)
+  # xhtml4Tr:: XHTML 1.0 Transitional
+  # xhtml4Fr:: XHTML 1.0 with Framesets
   #
   # If not specified, no HTML generation methods will be loaded.
   #
@@ -2291,6 +2552,20 @@
       extend Html4Fr
       element_init()
       extend HtmlExtension
+    when 'xhtml10'
+      extend Xhtml10
+      element_init()
+      extend HtmlExtension
+    when 'xhtml10Tr'
+      extend Xhtml10Tr
+      element_init()
+      extend HtmlExtension
+    when 'xhtml10Fr'
+      extend Xhtml10Tr
+      element_init()
+      extend Xhtml10Fr
+      element_init()
+      extend HtmlExtension
     end
   end