Index: C:/opensource/projects/castor/src/main/java/org/exolab/castor/xml/Marshaller.java
===================================================================
--- C:/opensource/projects/castor/src/main/java/org/exolab/castor/xml/Marshaller.java	(revision 6121)
+++ C:/opensource/projects/castor/src/main/java/org/exolab/castor/xml/Marshaller.java	(working copy)
@@ -88,6 +88,7 @@
 //import java.io.Serializable;
 import java.io.Writer;
 import java.lang.reflect.Array;
+import java.lang.reflect.Proxy;
 import java.util.Enumeration;
 
 
@@ -922,8 +923,53 @@
         
         Class _class = null;
         
-        if (!isNil) {
-            _class = object.getClass();
+        if (!isNil) 
+        {
+        	/*
+        	 * Check to see if this is a Proxied object, if it is, it needs to be handled special
+        	 * 
+        	 * Fetch all the interfaces on the Proxied Object, see if you can find a match in 
+        	 * the XMLMapping for the given interface. 
+        	 * If you do, return the interface class else return the proxy class 
+        	 * 
+        	 * Need to set the class attribute verify-constructable="false" on the Mapped interface.
+        	 * 
+        	 * Limitations:
+        	 * 	A proxy can proxy more then one interface. 
+        	 *  If you have mappings for more then one of the interfaces in the mapping file, it will
+        	 *  choose the first match in the Proxy -> Class[] interfaces
+        	 * 
+        	 */
+        	if(Proxy.isProxyClass(object.getClass()))
+        	{
+        		if(this._debug)System.out.println("Current object is a proxy class");
+        		XMLMappingLoader ml = (XMLMappingLoader) _cdResolver.getMappingLoader();
+                if (ml != null)
+                {
+                	Class[] interfaces = object.getClass().getInterfaces(); 
+	        		for(int i = 0; i < interfaces.length; i++)
+	        		{
+	        			Class interfaceClass = interfaces[i];
+	        			if(this._debug)System.out.println("Looking up interface on proxy: " + interfaceClass.getName());
+	        			if(ml.getDescriptor(interfaceClass.getName()) != null)
+	        			{
+	        				if(this._debug)System.out.println("Found mapping for interface " + interfaceClass.getName());
+	        				_class = interfaceClass;
+	        				break;
+	        			}
+	        		}
+	        		if(_class == null)
+	        		{
+	        			if(_debug)
+	        				System.out.println("No mapped interface found on proxy class.. using proxy class");
+	        			_class = object.getClass(); 
+	        		}
+                }
+                else
+                	if(this._debug)System.out.println("No XMLMappingLoader found");
+        	}
+        	else
+        		_class = object.getClass();
         }
         else {
             _class = ((NilObject)object).getClassDescriptor().getJavaClass();
Index: C:/opensource/projects/castor/src/main/java/org/exolab/castor/util/DefaultObjectFactory.java
===================================================================
--- C:/opensource/projects/castor/src/main/java/org/exolab/castor/util/DefaultObjectFactory.java	(revision 6121)
+++ C:/opensource/projects/castor/src/main/java/org/exolab/castor/util/DefaultObjectFactory.java	(working copy)
@@ -110,6 +110,15 @@
             if (java.util.Date.class.isAssignableFrom(type)) {
                 return handleDates(type);
             }
+            /*
+             * If the type is an interface we can't make a normal instanace of using .newInstance()
+             * 
+             * We fake a new instance via a proxy..
+             */
+            if(type.isInterface())
+            {
+            	return DynamicInstance.getInstance(type);
+            }
             return type.newInstance();
         }
         
Index: C:/opensource/projects/castor/src/main/java/org/exolab/castor/util/DynamicInstance.java
===================================================================
--- C:/opensource/projects/castor/src/main/java/org/exolab/castor/util/DynamicInstance.java	(revision 0)
+++ C:/opensource/projects/castor/src/main/java/org/exolab/castor/util/DynamicInstance.java	(revision 0)
@@ -0,0 +1,102 @@
+package org.exolab.castor.util;
+
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+import java.util.HashMap;
+import java.util.Map;
+
+/*
+ * Helper class to make runtime instances of valueobjects.
+ * 
+ * Returns a proxied interface.
+ * 
+ * Example of lookup:
+ * Signature	Name		Type
+ * --------------------------------
+ * getMethod	Method    	GET
+ * setMethod 	Method		SET
+ * getName		Name		GET
+ * setName		Name		SET
+ * 
+ * setMethods put value to the internal values Map
+ * getMethods get value from the internal values Map
+ */
+public class DynamicInstance implements InvocationHandler {
+
+	public static Object getInstance(final Class inter)
+	{
+		if(inter == null)
+			return null;
+		
+		return Proxy.newProxyInstance(
+					inter.getClassLoader(), 
+					new Class[] {inter}, 
+					new DynamicInstance());
+	}
+
+	private Map values; 	//  <String, Object>
+	
+	private DynamicInstance()
+	{
+		this.values = new HashMap(); 	//  <String, Object>
+	}
+	
+	public final int TypeSET 		= 0;
+	public final int TypeGET 		= 1;
+	public final int TypeOTHER		= 2;
+	
+	public Object invoke(final Object object, final Method method, final Object[] arguments) 
+		throws Throwable 
+	{
+		int methodType = getMethodType(method);
+		
+		// no clue witch to return on the get if there is more then one parameter to set
+		if(methodType == TypeSET && (arguments != null && arguments.length != 1))
+			throw new IllegalArgumentException("only handles set methods with one parmeter");
+		
+		switch(methodType)
+		{
+			case TypeSET: 
+				setValue(getMethodName(method), arguments[0]);
+				break;
+			case TypeGET:
+			{
+				Object result = getValue(getMethodName(method));
+				return result;
+			}
+		}
+		return null;
+	}
+	
+	private Object getValue(String name)
+	{
+		return this.values.get(name);
+	}
+	
+	private void setValue(String name, Object object)
+	{
+		this.values.put(name, object);
+	}
+	
+	private int getMethodType(Method method)
+	{
+		String methodName = method.getName();
+		if(methodName.startsWith("set"))
+			return TypeSET;
+		if(methodName.startsWith("get"))
+			return TypeGET;
+
+		return TypeOTHER;
+	}
+
+	private String getMethodName(Method method)
+	{
+		String methodName = method.getName();
+		if(methodName.startsWith("set"))
+			return methodName.substring(3);
+		if(methodName.startsWith("get"))
+			return methodName.substring(3);
+		return null;
+	}
+}