diff --git a/src/main/org/apache/tools/ant/taskdefs/AntStructure.java b/src/main/org/apache/tools/ant/taskdefs/AntStructure.java
new file mode 100644
index 000000000..7e80c8b71
--- /dev/null
+++ b/src/main/org/apache/tools/ant/taskdefs/AntStructure.java
@@ -0,0 +1,261 @@
+/*
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution, if
+ *    any, must include the following acknowlegement:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowlegement may appear in the software itself,
+ *    if and wherever such third-party acknowlegements normally appear.
+ *
+ * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
+ *    Foundation" must not be used to endorse or promote products derived
+ *    from this software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache"
+ *    nor may "Apache" appear in their names without prior written
+ *    permission of the Apache Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ */
+
+package org.apache.tools.ant.taskdefs;
+
+import org.apache.tools.ant.*;
+
+import java.util.Enumeration;
+import java.util.Hashtable;
+import java.util.Vector;
+import java.io.*;
+
+/**
+ * Creates a partial DTD for Ant from the currently known tasks.
+ *
+ * @author Stefan Bodewig <a href="mailto:stefan.bodewig@megabit.net">stefan.bodewig@megabit.net</a>
+ */
+
+public class AntStructure extends Task {
+
+    private final String lSep = System.getProperty("line.separator");
+
+    private Hashtable visited = new Hashtable();
+
+    private File output;
+
+    /**
+     * The output file.
+     */
+    public void setOutput(File output) {
+        this.output = output;
+    }
+
+    public void execute() throws BuildException {
+
+        if (output == null) {
+            throw new BuildException("output attribute is required", location);
+        }
+        
+        PrintWriter out = null;
+        try {
+            try {
+                out = new PrintWriter(new OutputStreamWriter(new FileOutputStream(output), "ISO8859_1"));
+            } catch (UnsupportedEncodingException ue) {
+                /*
+                 * Plain impossible with ISO8859_1, see
+                 * http://java.sun.com/products/jdk/1.2/docs/guide/internat/encoding.doc.html
+                 *
+                 * fallback to platform specific anyway.
+                 */
+                out = new PrintWriter(new FileWriter(output));
+            }
+            
+            printHead(out);
+
+            Vector tasks = new Vector();
+            Enumeration enum = project.getTaskDefinitions().keys();
+            while (enum.hasMoreElements()) {
+                String taskName = (String) enum.nextElement();
+                tasks.add(taskName);
+            }
+            printTargetDecl(out, tasks);
+
+            for (int i=0; i<tasks.size(); i++) {
+                String taskName = (String) tasks.elementAt(i);
+                printElementDecl(out, taskName, 
+                                 (Class) project.getTaskDefinitions().get(taskName));
+            }
+
+            printTail(out);
+
+        } catch (IOException ioe) {
+            throw new BuildException("Error writing "+output.getAbsolutePath(),
+                                     ioe, location);
+        } finally {
+            if (out != null) {
+                out.close();
+            }
+        }
+    }
+
+    private void printHead(PrintWriter out) {
+        out.println("<?xml version=\"1.0\" encoding=\"iso-8859-1\"?>");
+        out.println("<!ENTITY % boolean \"(true|false|on|off|yes|no)\">");
+        out.println("");
+        
+        out.println("<!ELEMENT project (target | property | taskdef)*>");
+        out.println("<!ATTLIST project");
+        out.println("          name    CDATA #REQUIRED");
+        out.println("          default CDATA #REQUIRED");
+        out.println("          basedir CDATA #IMPLIED>");
+        out.println("");
+    }
+
+    private void printTargetDecl(PrintWriter out, Vector tasks) {
+        out.print("<!ELEMENT target (");
+        for (int i=0; i<tasks.size(); i++) {
+            String taskName = (String) tasks.elementAt(i);
+            if (i > 0) {
+                out.print(" | ");
+            }
+            out.print(taskName);
+        }
+                 
+        out.println(")*>");
+        out.println("");
+
+        out.println("<!ATTLIST target");
+        out.println("          id      ID    #IMPLIED");
+        out.println("          name    CDATA #REQUIRED");
+        out.println("          if      CDATA #IMPLIED");
+        out.println("          unless  CDATA #IMPLIED");
+        out.println("          depends CDATA #IMPLIED>");
+        out.println("");
+    }
+
+    private void printElementDecl(PrintWriter out, String name, Class element) 
+        throws BuildException {
+
+        if (visited.containsKey(name)) {
+            return;
+        }
+        visited.put(name, "");
+
+        IntrospectionHelper ih = IntrospectionHelper.getHelper(element);
+
+        StringBuffer sb = new StringBuffer("<!ELEMENT ");
+        sb.append(name).append(" ");
+
+        Vector v = new Vector();
+        if (ih.supportsCharacters()) {
+            v.addElement("#PCDATA");
+        }
+
+        Enumeration enum = ih.getNestedElements();
+        while (enum.hasMoreElements()) {
+            v.addElement((String) enum.nextElement());
+        }
+
+        if (v.isEmpty()) {
+            sb.append("EMPTY");
+        } else {
+            sb.append("(");
+            for (int i=0; i<v.size(); i++) {
+                if (i != 0) {
+                    sb.append(" | ");
+                }
+                sb.append(v.elementAt(i));
+            }
+            sb.append(")");
+            if (v.size() > 1 || !v.elementAt(0).equals("#PCDATA")) {
+                sb.append("*");
+            }
+        }
+        sb.append(">");
+        out.println(sb);
+
+        sb.setLength(0);
+        sb.append("<!ATTLIST ").append(name);
+        sb.append(lSep).append("          id ID #IMPLIED");
+        
+        enum = ih.getAttributes();
+        while (enum.hasMoreElements()) {
+            String attrName = (String) enum.nextElement();
+            sb.append(lSep).append("          ").append(attrName).append(" ");
+            Class type = ih.getAttributeType(attrName);
+            if (type.equals(java.lang.Boolean.class) || 
+                type.equals(java.lang.Boolean.TYPE)) {
+                sb.append("%boolean; ");
+            } else if (org.apache.tools.ant.EnumeratedAttribute.class.isAssignableFrom(type)) {
+                try {
+                    EnumeratedAttribute ea = 
+                        (EnumeratedAttribute)type.newInstance();
+                    String[] values = ea.getValues();
+                    if (values == null || values.length == 0) {
+                        sb.append("CDATA ");
+                    } else {
+                        sb.append("(");
+                        for (int i=0; i < values.length; i++) {
+                            if (i != 0) {
+                                sb.append(" | ");
+                            }
+                            sb.append(values[i]);
+                        }
+                        sb.append(") ");
+                    }
+                } catch (InstantiationException ie) {
+                    sb.append("CDATA ");
+                } catch (IllegalAccessException ie) {
+                    sb.append("CDATA ");
+                }
+            } else {
+                sb.append("CDATA ");
+            }
+            sb.append("#IMPLIED");
+        }
+        sb.append(">").append(lSep);
+        out.println(sb);
+
+        for (int i=0; i<v.size(); i++) {
+            String nestedName = (String) v.elementAt(i);
+            if (!"#PCDATA".equals(nestedName)) {
+                printElementDecl(out, nestedName, ih.getElementType(nestedName));
+            }
+        }
+    }
+    
+    private void printTail(PrintWriter out) {}
+
+}
diff --git a/src/main/org/apache/tools/ant/taskdefs/defaults.properties b/src/main/org/apache/tools/ant/taskdefs/defaults.properties
index e7bb1af2d..ad7aa7f69 100644
--- a/src/main/org/apache/tools/ant/taskdefs/defaults.properties
+++ b/src/main/org/apache/tools/ant/taskdefs/defaults.properties
@@ -35,6 +35,7 @@ compileTask=org.apache.tools.ant.taskdefs.CompileTask
 style=org.apache.tools.ant.taskdefs.XSLTProcess
 touch=org.apache.tools.ant.taskdefs.Touch
 signjar=org.apache.tools.ant.taskdefs.SignJar
+antstructure=org.apache.tools.ant.taskdefs.AntStructure
 
 # optional tasks
 script=org.apache.tools.ant.taskdefs.optional.Script