diff --git a/library/HTMLPurifier/AttrCollection.php b/library/HTMLPurifier/AttrCollection.php
index c92081af..3239e2f4 100644
--- a/library/HTMLPurifier/AttrCollection.php
+++ b/library/HTMLPurifier/AttrCollection.php
@@ -47,7 +47,7 @@ class HTMLPurifier_AttrCollection
             // merge attribute collections that include others
             $this->performInclusions($info[$name]);
             // replace string identifiers with actual attribute objects
-            $this->expandStringIdentifiers($info[$name], $attr_types);
+            $this->expandIdentifiers($info[$name], $attr_types);
         }
     }
     
@@ -69,7 +69,7 @@ class HTMLPurifier_AttrCollection
         unset($attr[0]);
     }
     
-    function expandStringIdentifiers(&$attr, $attr_types) {
+    function expandIdentifiers(&$attr, $attr_types) {
         foreach ($attr as $def_i => $def) {
             if ($def_i === 0) continue;
             if (!is_string($def)) continue;
diff --git a/library/HTMLPurifier/AttrTypes.php b/library/HTMLPurifier/AttrTypes.php
index 95819776..59ed4e56 100644
--- a/library/HTMLPurifier/AttrTypes.php
+++ b/library/HTMLPurifier/AttrTypes.php
@@ -14,8 +14,11 @@ class HTMLPurifier_AttrTypes
     function HTMLPurifier_AttrTypes() {
         $this->info['NMTOKENS'] = new HTMLPurifier_AttrDef_Nmtokens();
         $this->info['CDATA'] = new HTMLPurifier_AttrDef_Text();
+        $this->info['Text'] = new HTMLPurifier_AttrDef_Text();
         $this->info['ID'] = new HTMLPurifier_AttrDef_ID();
         $this->info['URI'] = new HTMLPurifier_AttrDef_URI();
+        $this->info['Pixels'] = new HTMLPurifier_AttrDef_Pixels();
+        $this->info['Length'] = new HTMLPurifier_AttrDef_Length();
     }
 }
 
diff --git a/library/HTMLPurifier/HTMLModule/Tables.php b/library/HTMLPurifier/HTMLModule/Tables.php
new file mode 100644
index 00000000..10263a2a
--- /dev/null
+++ b/library/HTMLPurifier/HTMLModule/Tables.php
@@ -0,0 +1,76 @@
+<?php
+
+require_once 'HTMLPurifier/HTMLModule.php';
+
+/**
+ * XHTML 1.1 Tables Module, fully defines accessible table elements.
+ */
+class HTMLPurifier_HTMLModule_Tables extends HTMLPurifier_HTMLModule
+{
+    
+    var $elements = array('caption', 'table', 'td', 'th', 'tr', 'col',
+        'colgroup', 'tbody', 'thead', 'tfoot');
+    var $info = array();
+    var $content_sets = array('Block' => 'table');
+    
+    function HTMLPurifier_HTMLModule_Tables() {
+        foreach ($this->elements as $e) {
+            $this->info[$e] = new HTMLPurifier_ElementDef();
+            $this->info[$e]->attr = array(0 => array('Common'));
+            $attr =& $this->info[$e]->attr;
+            if ($e == 'caption') continue;
+            if ($e == 'table'){
+                $attr['border'] = 'Pixels';
+                $attr['cellpadding'] = 'Length';
+                $attr['cellspacing'] = 'Length';
+                $attr['frame'] = new HTMLPurifier_AttrDef_Enum(array(
+                    'void', 'above', 'below', 'hsides', 'lhs', 'rhs',
+                    'vsides', 'box', 'border'
+                ), false);
+                $attr['rules'] = new HTMLPurifier_AttrDef_Enum(array(
+                    'none', 'groups', 'rows', 'cols', 'all'
+                ), false);
+                $attr['summary'] = 'Text';
+                $attr['width'] = 'Length';
+                continue;
+            }
+            if ($e == 'td' || $e == 'th') $attr['abbr'] = 'Text';
+            $attr['align'] = new HTMLPurifier_AttrDef_Enum(array(
+                'left', 'center', 'right', 'justify', 'char'
+            ), false);
+            $attr['valign'] = new HTMLPurifier_AttrDef_Enum(array(
+                'top', 'middle', 'bottom', 'baseline'
+            ), false);
+            $attr['charoff'] = 'Length';
+        }
+        $this->info['caption']->content_model = '#PCDATA | Inline';
+        $this->info['caption']->content_model_type = 'optional';
+        
+        $this->info['table']->content_model = 'caption?, ( col* | colgroup* ), (( thead?, tfoot?, tbody+ ) | ( tr+ ))';
+        $this->info['table']->content_model_type = 'table';
+        
+        $this->info['td']->content_model = 
+        $this->info['th']->content_model = '#PCDATA | Flow';
+        $this->info['td']->content_model_type = 
+        $this->info['th']->content_model_type = 'optional';
+        
+        $this->info['tr']->content_model = 'td | th';
+        $this->info['tr']->content_model_type = 'required';
+        
+        $this->info['col']->content_model_type = 'empty';
+        
+        $this->info['colgroup']->content_model = 'col';
+        $this->info['colgroup']->content_model_type = 'optional';
+        
+        $this->info['tbody']->content_model = 
+        $this->info['thead']->content_model = 
+        $this->info['tfoot']->content_model = 'tr';
+        $this->info['tbody']->content_model_type = 
+        $this->info['thead']->content_model_type = 
+        $this->info['tfoot']->content_model_type = 'required';
+        
+    }
+    
+}
+
+?>
\ No newline at end of file
diff --git a/library/HTMLPurifier/Printer/HTMLDefinition.php b/library/HTMLPurifier/Printer/HTMLDefinition.php
index c7314bcd..fb1a357f 100644
--- a/library/HTMLPurifier/Printer/HTMLDefinition.php
+++ b/library/HTMLPurifier/Printer/HTMLDefinition.php
@@ -143,8 +143,8 @@ class HTMLPurifier_Printer_HTMLDefinition extends HTMLPurifier_Printer
             } elseif ($def->type == 'empty') {
                 $elements = array();
             } elseif ($def->type == 'table') {
-                $elements = array('col', 'caption', 'colgroup', 'thead',
-                    'tfoot', 'tbody', 'tr');
+                $elements = array_flip(array('col', 'caption', 'colgroup', 'thead',
+                    'tfoot', 'tbody', 'tr'));
             }
             $ret .= $this->element('th', 'Allowed children', $attr);
             
diff --git a/library/HTMLPurifier/XHTMLDefinition.php b/library/HTMLPurifier/XHTMLDefinition.php
index 144a8ccf..2cd72d67 100644
--- a/library/HTMLPurifier/XHTMLDefinition.php
+++ b/library/HTMLPurifier/XHTMLDefinition.php
@@ -12,6 +12,7 @@ require_once 'HTMLPurifier/HTMLModule/List.php';
 require_once 'HTMLPurifier/HTMLModule/Presentation.php';
 require_once 'HTMLPurifier/HTMLModule/Edit.php';
 require_once 'HTMLPurifier/HTMLModule/Bdo.php';
+require_once 'HTMLPurifier/HTMLModule/Tables.php';
 
 /**
  * Next-generation HTML definition that will supplant HTMLPurifier_HTMLDefinition
@@ -32,6 +33,7 @@ class HTMLPurifier_XHTMLDefinition extends HTMLPurifier_HTMLDefinition
         $this->modules['Presentation']  = new HTMLPurifier_HTMLModule_Presentation();
         $this->modules['Edit']          = new HTMLPurifier_HTMLModule_Edit();
         $this->modules['Bdo']           = new HTMLPurifier_HTMLModule_Bdo();
+        $this->modules['Tables']        = new HTMLPurifier_HTMLModule_Tables();
         
         $this->attr_types = new HTMLPurifier_AttrTypes();
         $this->attr_collection = new HTMLPurifier_AttrCollection();
@@ -80,7 +82,7 @@ class HTMLPurifier_XHTMLDefinition extends HTMLPurifier_HTMLDefinition
                 
                 // attribute value expansions
                 $this->attr_collection->performInclusions($def->attr);
-                $this->attr_collection->expandStringIdentifiers(
+                $this->attr_collection->expandIdentifiers(
                     $def->attr, $this->attr_types);
                 
                 // perform content model expansions
@@ -156,7 +158,7 @@ class HTMLPurifier_XHTMLDefinition extends HTMLPurifier_HTMLDefinition
                 return new HTMLPurifier_ChildDef_Custom($value);
         }
         if ($value) return new HTMLPurifier_ChildDef_Optional($value);
-        return HTMLPurifier_ChildDef_Empty();
+        return new HTMLPurifier_ChildDef_Empty();
     }
     
     function convertToLookup($string) {