make antlib compile against Ant master
diff --git a/src/main/org/apache/ant/compress/resources/CommonsCompressFileSet.java b/src/main/org/apache/ant/compress/resources/CommonsCompressFileSet.java
index 7a51bf5..25a96aa 100644
--- a/src/main/org/apache/ant/compress/resources/CommonsCompressFileSet.java
+++ b/src/main/org/apache/ant/compress/resources/CommonsCompressFileSet.java
@@ -223,11 +223,11 @@
      * as this one.
      * @return the cloned tarFileSet
      */
-    public Object clone() {
+    public CommonsCompressFileSet clone() {
         if (isReference()) {
             return ((CommonsCompressFileSet) getRef(getProject())).clone();
         } else {
-            return super.clone();
+            return (CommonsCompressFileSet) super.clone();
         }
     }