diff --git a/proposal/mutant/src/java/antcore/org/apache/ant/antcore/execution/Frame.java b/proposal/mutant/src/java/antcore/org/apache/ant/antcore/execution/Frame.java
index 39a5e057b..41c593aef 100644
--- a/proposal/mutant/src/java/antcore/org/apache/ant/antcore/execution/Frame.java
+++ b/proposal/mutant/src/java/antcore/org/apache/ant/antcore/execution/Frame.java
@@ -943,7 +943,7 @@ public class Frame {
                 throw new ExecutionException("The given ant:refid value '"
                      + refId + "' is not defined", model.getLocation());
             }
-        } else {
+        } else if (nestedType != null) {
             // We need to create an instance of the class expected by the nested
             // element's adder method if that is possible
             if (nestedType.isInterface()) {
@@ -954,6 +954,12 @@ public class Frame {
             }
 
             typeInstance = createTypeInstance(nestedType, factory, model, null);
+        } else {
+            throw new ExecutionException("The type of the <" 
+                + nestedElementName + "> nested element is not known. "
+                + "Please specify by the type using the \"ant:type\" " 
+                + "attribute or provide a reference to an instance with " 
+                + "the \"ant:id\" attribute");
         }
 
         // is the typeInstance compatible with the type expected
diff --git a/proposal/mutant/src/java/antlibs/script/org/apache/ant/antlib/script/ScriptBase.java b/proposal/mutant/src/java/antlibs/script/org/apache/ant/antlib/script/ScriptBase.java
index 2af7b619f..d7c2e0248 100644
--- a/proposal/mutant/src/java/antlibs/script/org/apache/ant/antlib/script/ScriptBase.java
+++ b/proposal/mutant/src/java/antlibs/script/org/apache/ant/antlib/script/ScriptBase.java
@@ -120,9 +120,12 @@ public class ScriptBase extends AbstractTask implements DeferredTask {
 
         try {
             BSFManager manager = new BSFManager();
-
+            manager.declareBean("self", this, getClass());
+            manager.declareBean("context", getContext, AntContext.class);
+            
             // execute the script
             BSFEngine engine = manager.loadScriptingEngine(language);
+            
             engine.exec(scriptName, 0, 0, script);
             for (Iterator i = attributes.keySet().iterator(); i.hasNext(); ) {
                 String attributeName = (String)i.next();
@@ -131,6 +134,17 @@ public class ScriptBase extends AbstractTask implements DeferredTask {
                 setter.setCharAt(0, Character.toUpperCase(setter.charAt(0)));
                 engine.call(null, "set" + setter, new Object[]{value});
             }
+            
+            Iterator i = nestedElementNames.iterator();
+            Iterator j = nestedElements.iterator();
+            while (i.hasNext()) {
+                String nestedName = (String)i.next();
+                Object nestedElement = j.next();
+                StringBuffer adder = new StringBuffer(nestedName);
+                adder.setCharAt(0, Character.toUpperCase(adder.charAt(0)));
+                engine.call(null, "add" + adder, new Object[]{nestedElement});
+            }
+            
             engine.call(null, "execute", new Object[]{});
         } catch (BSFException e) {
             Throwable t = e;
diff --git a/proposal/mutant/src/java/common/org/apache/ant/common/service/ComponentService.java b/proposal/mutant/src/java/common/org/apache/ant/common/service/ComponentService.java
index b35e571d5..8942e801b 100644
--- a/proposal/mutant/src/java/common/org/apache/ant/common/service/ComponentService.java
+++ b/proposal/mutant/src/java/common/org/apache/ant/common/service/ComponentService.java
@@ -95,7 +95,7 @@ public interface ComponentService {
     void addLibPath(String libraryId, URL libPath) throws ExecutionException;
 
     /**
-     * Experimental - define a new type
+     * Define a new type
      *
      * @param typeName the name by which this type will be referred
      * @param factory the library factory object to create the type