diff --git a/xml/xmldsig-core-schema.xsd b/xml/xmldsig-core-schema.xsd
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+++ b/xml/xmldsig-core-schema.xsd
@@ -0,0 +1,317 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!DOCTYPE schema
+ [
+   <!ATTLIST schema 
+     xmlns:ds CDATA #FIXED "http://www.w3.org/2000/09/xmldsig#">
+   <!ENTITY dsig 'http://www.w3.org/2000/09/xmldsig#'>
+   <!ENTITY % p ''>
+   <!ENTITY % s ''>
+  ]>
+
+<!-- Schema for XML Signatures
+    http://www.w3.org/2000/09/xmldsig#
+    $Revision: 1.1 $ on $Date: 2005/03/16 17:40:08 $ by $Author: iay $
+
+    Copyright 2001 The Internet Society and W3C (Massachusetts Institute
+    of Technology, Institut National de Recherche en Informatique et en
+    Automatique, Keio University). All Rights Reserved.
+    http://www.w3.org/Consortium/Legal/
+
+    This document is governed by the W3C Software License [1] as described
+    in the FAQ [2].
+
+    [1] http://www.w3.org/Consortium/Legal/copyright-software-19980720
+    [2] http://www.w3.org/Consortium/Legal/IPR-FAQ-20000620.html#DTD
+-->
+
+
+<schema xmlns="http://www.w3.org/2001/XMLSchema"
+        xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
+        targetNamespace="http://www.w3.org/2000/09/xmldsig#"
+        version="0.1" elementFormDefault="qualified"> 
+
+<!-- Basic Types Defined for Signatures -->
+
+<simpleType name="CryptoBinary">
+  <restriction base="base64Binary">
+  </restriction>
+</simpleType>
+
+<!-- Start Signature -->
+
+<element name="Signature" type="ds:SignatureType"/>
+<complexType name="SignatureType">
+  <sequence> 
+    <element ref="ds:SignedInfo"/> 
+    <element ref="ds:SignatureValue"/> 
+    <element ref="ds:KeyInfo" minOccurs="0"/> 
+    <element ref="ds:Object" minOccurs="0" maxOccurs="unbounded"/> 
+  </sequence>  
+  <attribute name="Id" type="ID" use="optional"/>
+</complexType>
+
+  <element name="SignatureValue" type="ds:SignatureValueType"/> 
+  <complexType name="SignatureValueType">
+    <simpleContent>
+      <extension base="base64Binary">
+        <attribute name="Id" type="ID" use="optional"/>
+      </extension>
+    </simpleContent>
+  </complexType>
+
+<!-- Start SignedInfo -->
+
+<element name="SignedInfo" type="ds:SignedInfoType"/>
+<complexType name="SignedInfoType">
+  <sequence> 
+    <element ref="ds:CanonicalizationMethod"/> 
+    <element ref="ds:SignatureMethod"/> 
+    <element ref="ds:Reference" maxOccurs="unbounded"/> 
+  </sequence>  
+  <attribute name="Id" type="ID" use="optional"/> 
+</complexType>
+
+  <element name="CanonicalizationMethod" type="ds:CanonicalizationMethodType"/> 
+  <complexType name="CanonicalizationMethodType" mixed="true">
+    <sequence>
+      <any namespace="##any" minOccurs="0" maxOccurs="unbounded"/>
+      <!-- (0,unbounded) elements from (1,1) namespace -->
+    </sequence>
+    <attribute name="Algorithm" type="anyURI" use="required"/> 
+  </complexType>
+
+  <element name="SignatureMethod" type="ds:SignatureMethodType"/>
+  <complexType name="SignatureMethodType" mixed="true">
+    <sequence>
+      <element name="HMACOutputLength" minOccurs="0" type="ds:HMACOutputLengthType"/>
+      <any namespace="##other" minOccurs="0" maxOccurs="unbounded"/>
+      <!-- (0,unbounded) elements from (1,1) external namespace -->
+    </sequence>
+    <attribute name="Algorithm" type="anyURI" use="required"/> 
+  </complexType>
+
+<!-- Start Reference -->
+
+<element name="Reference" type="ds:ReferenceType"/>
+<complexType name="ReferenceType">
+  <sequence> 
+    <element ref="ds:Transforms" minOccurs="0"/> 
+    <element ref="ds:DigestMethod"/> 
+    <element ref="ds:DigestValue"/> 
+  </sequence>
+  <attribute name="Id" type="ID" use="optional"/> 
+  <attribute name="URI" type="anyURI" use="optional"/> 
+  <attribute name="Type" type="anyURI" use="optional"/> 
+</complexType>
+
+  <element name="Transforms" type="ds:TransformsType"/>
+  <complexType name="TransformsType">
+    <sequence>
+      <element ref="ds:Transform" maxOccurs="unbounded"/>  
+    </sequence>
+  </complexType>
+
+  <element name="Transform" type="ds:TransformType"/>
+  <complexType name="TransformType" mixed="true">
+    <choice minOccurs="0" maxOccurs="unbounded"> 
+      <any namespace="##other" processContents="lax"/>
+      <!-- (1,1) elements from (0,unbounded) namespaces -->
+      <element name="XPath" type="string"/> 
+    </choice>
+    <attribute name="Algorithm" type="anyURI" use="required"/> 
+  </complexType>
+
+<!-- End Reference -->
+
+<element name="DigestMethod" type="ds:DigestMethodType"/>
+<complexType name="DigestMethodType" mixed="true"> 
+  <sequence>
+    <any namespace="##other" processContents="lax" minOccurs="0" maxOccurs="unbounded"/>
+  </sequence>    
+  <attribute name="Algorithm" type="anyURI" use="required"/> 
+</complexType>
+
+<element name="DigestValue" type="ds:DigestValueType"/>
+<simpleType name="DigestValueType">
+  <restriction base="base64Binary"/>
+</simpleType>
+
+<!-- End SignedInfo -->
+
+<!-- Start KeyInfo -->
+
+<element name="KeyInfo" type="ds:KeyInfoType"/> 
+<complexType name="KeyInfoType" mixed="true">
+  <choice maxOccurs="unbounded">     
+    <element ref="ds:KeyName"/> 
+    <element ref="ds:KeyValue"/> 
+    <element ref="ds:RetrievalMethod"/> 
+    <element ref="ds:X509Data"/> 
+    <element ref="ds:PGPData"/> 
+    <element ref="ds:SPKIData"/>
+    <element ref="ds:MgmtData"/>
+    <any processContents="lax" namespace="##other"/>
+    <!-- (1,1) elements from (0,unbounded) namespaces -->
+  </choice>
+  <attribute name="Id" type="ID" use="optional"/> 
+</complexType>
+
+  <element name="KeyName" type="string"/>
+  <element name="MgmtData" type="string"/>
+
+  <element name="KeyValue" type="ds:KeyValueType"/> 
+  <complexType name="KeyValueType" mixed="true">
+   <choice>
+     <element ref="ds:DSAKeyValue"/>
+     <element ref="ds:RSAKeyValue"/>
+     <any namespace="##other" processContents="lax"/>
+   </choice>
+  </complexType>
+
+  <element name="RetrievalMethod" type="ds:RetrievalMethodType"/> 
+  <complexType name="RetrievalMethodType">
+    <sequence>
+      <element ref="ds:Transforms" minOccurs="0"/> 
+    </sequence>  
+    <attribute name="URI" type="anyURI"/>
+    <attribute name="Type" type="anyURI" use="optional"/>
+  </complexType>
+
+<!-- Start X509Data -->
+
+<element name="X509Data" type="ds:X509DataType"/> 
+<complexType name="X509DataType">
+  <sequence maxOccurs="unbounded">
+    <choice>
+      <element name="X509IssuerSerial" type="ds:X509IssuerSerialType"/>
+      <element name="X509SKI" type="base64Binary"/>
+      <element name="X509SubjectName" type="string"/>
+      <element name="X509Certificate" type="base64Binary"/>
+      <element name="X509CRL" type="base64Binary"/>
+      <any namespace="##other" processContents="lax"/>
+    </choice>
+  </sequence>
+</complexType>
+
+<complexType name="X509IssuerSerialType"> 
+  <sequence> 
+    <element name="X509IssuerName" type="string"/> 
+    <element name="X509SerialNumber" type="integer"/> 
+  </sequence>
+</complexType>
+
+<!-- End X509Data -->
+
+<!-- Begin PGPData -->
+
+<element name="PGPData" type="ds:PGPDataType"/> 
+<complexType name="PGPDataType"> 
+  <choice>
+    <sequence>
+      <element name="PGPKeyID" type="base64Binary"/> 
+      <element name="PGPKeyPacket" type="base64Binary" minOccurs="0"/> 
+      <any namespace="##other" processContents="lax" minOccurs="0"
+       maxOccurs="unbounded"/>
+    </sequence>
+    <sequence>
+      <element name="PGPKeyPacket" type="base64Binary"/> 
+      <any namespace="##other" processContents="lax" minOccurs="0"
+       maxOccurs="unbounded"/>
+    </sequence>
+  </choice>
+</complexType>
+
+<!-- End PGPData -->
+
+<!-- Begin SPKIData -->
+
+<element name="SPKIData" type="ds:SPKIDataType"/> 
+<complexType name="SPKIDataType">
+  <sequence maxOccurs="unbounded">
+    <element name="SPKISexp" type="base64Binary"/>
+    <any namespace="##other" processContents="lax" minOccurs="0"/>
+  </sequence>
+</complexType> 
+
+<!-- End SPKIData -->
+
+<!-- End KeyInfo -->
+
+<!-- Start Object (Manifest, SignatureProperty) -->
+
+<element name="Object" type="ds:ObjectType"/> 
+<complexType name="ObjectType" mixed="true">
+  <sequence minOccurs="0" maxOccurs="unbounded">
+    <any namespace="##any" processContents="lax"/>
+  </sequence>
+  <attribute name="Id" type="ID" use="optional"/> 
+  <attribute name="MimeType" type="string" use="optional"/> <!-- add a grep facet -->
+  <attribute name="Encoding" type="anyURI" use="optional"/> 
+</complexType>
+
+<element name="Manifest" type="ds:ManifestType"/> 
+<complexType name="ManifestType">
+  <sequence>
+    <element ref="ds:Reference" maxOccurs="unbounded"/> 
+  </sequence>
+  <attribute name="Id" type="ID" use="optional"/> 
+</complexType>
+
+<element name="SignatureProperties" type="ds:SignaturePropertiesType"/> 
+<complexType name="SignaturePropertiesType">
+  <sequence>
+    <element ref="ds:SignatureProperty" maxOccurs="unbounded"/> 
+  </sequence>
+  <attribute name="Id" type="ID" use="optional"/> 
+</complexType>
+
+   <element name="SignatureProperty" type="ds:SignaturePropertyType"/> 
+   <complexType name="SignaturePropertyType" mixed="true">
+     <choice maxOccurs="unbounded">
+       <any namespace="##other" processContents="lax"/>
+       <!-- (1,1) elements from (1,unbounded) namespaces -->
+     </choice>
+     <attribute name="Target" type="anyURI" use="required"/> 
+     <attribute name="Id" type="ID" use="optional"/> 
+   </complexType>
+
+<!-- End Object (Manifest, SignatureProperty) -->
+
+<!-- Start Algorithm Parameters -->
+
+<simpleType name="HMACOutputLengthType">
+  <restriction base="integer"/>
+</simpleType>
+
+<!-- Start KeyValue Element-types -->
+
+<element name="DSAKeyValue" type="ds:DSAKeyValueType"/>
+<complexType name="DSAKeyValueType">
+  <sequence>
+    <sequence minOccurs="0">
+      <element name="P" type="ds:CryptoBinary"/>
+      <element name="Q" type="ds:CryptoBinary"/>
+    </sequence>
+    <element name="G" type="ds:CryptoBinary" minOccurs="0"/>
+    <element name="Y" type="ds:CryptoBinary"/>
+    <element name="J" type="ds:CryptoBinary" minOccurs="0"/>
+    <sequence minOccurs="0">
+      <element name="Seed" type="ds:CryptoBinary"/>
+      <element name="PgenCounter" type="ds:CryptoBinary"/>
+    </sequence>
+  </sequence>
+</complexType>
+
+<element name="RSAKeyValue" type="ds:RSAKeyValueType"/>
+<complexType name="RSAKeyValueType">
+  <sequence>
+    <element name="Modulus" type="ds:CryptoBinary"/> 
+    <element name="Exponent" type="ds:CryptoBinary"/> 
+  </sequence>
+</complexType> 
+
+<!-- End KeyValue Element-types -->
+
+<!-- End Signature -->
+
+</schema>