diff --git a/classpath/java/util/AbstractCollection.java b/classpath/java/util/AbstractCollection.java
index bc4abfe7a5..5093b9a612 100644
--- a/classpath/java/util/AbstractCollection.java
+++ b/classpath/java/util/AbstractCollection.java
@@ -33,7 +33,7 @@ public abstract class AbstractCollection<T> implements Collection<T> {
                                             + this.getClass().getName());
   }
 
-  public boolean contains(T element) {
+  public boolean contains(Object element) {
     if (element != null) {
       for (Iterator<T> iter = iterator(); iter.hasNext();) {
         if (element.equals(iter.next())) {
@@ -55,7 +55,7 @@ public abstract class AbstractCollection<T> implements Collection<T> {
     return size() == 0;
   }
 
-  public boolean remove(T element) {
+  public boolean remove(Object element) {
     throw new UnsupportedOperationException("remove(T) in "
                                             + this.getClass().getName());
   }
diff --git a/classpath/java/util/ArrayList.java b/classpath/java/util/ArrayList.java
index 00482f5722..d6ca7d07d3 100644
--- a/classpath/java/util/ArrayList.java
+++ b/classpath/java/util/ArrayList.java
@@ -66,7 +66,7 @@ public class ArrayList<T> implements List<T> {
     return size;
   }
 
-  public boolean contains(T element) {
+  public boolean contains(Object element) {
     for (int i = 0; i < size; ++i) {
       if (equal(element, array[i])) {
         return true;
@@ -145,7 +145,7 @@ public class ArrayList<T> implements List<T> {
     return v;
   }
 
-  public boolean remove(T element) {
+  public boolean remove(Object element) {
     for (int i = 0; i < size; ++i) {
       if (equal(element, array[i])) {
         remove(i);
diff --git a/classpath/java/util/Arrays.java b/classpath/java/util/Arrays.java
index af87139c8f..db41e6bddc 100644
--- a/classpath/java/util/Arrays.java
+++ b/classpath/java/util/Arrays.java
@@ -64,7 +64,7 @@ public class Arrays {
         throw new UnsupportedOperationException();
       }
 
-      public boolean contains(T element) {
+      public boolean contains(Object element) {
         for (int i = 0; i < array.length; ++i) {
           if (equal(element, array[i])) {
             return true;
@@ -93,7 +93,7 @@ public class Arrays {
         throw new UnsupportedOperationException();        
       }
 
-      public boolean remove(T element) {
+      public boolean remove(Object element) {
         throw new UnsupportedOperationException();
       }
 
diff --git a/classpath/java/util/Collection.java b/classpath/java/util/Collection.java
index cfde456aab..aa8eee6d89 100644
--- a/classpath/java/util/Collection.java
+++ b/classpath/java/util/Collection.java
@@ -15,13 +15,13 @@ public interface Collection<T> extends Iterable<T> {
 
   public boolean isEmpty();
 
-  public boolean contains(T element);
+  public boolean contains(Object element);
 
   public boolean add(T element);
 
   public boolean addAll(Collection<? extends T> collection);
 
-  public boolean remove(T element);
+  public boolean remove(Object element);
 
   public <S> S[] toArray(S[] array);
 
diff --git a/classpath/java/util/Collections.java b/classpath/java/util/Collections.java
index 134c481322..619a4c5c61 100644
--- a/classpath/java/util/Collections.java
+++ b/classpath/java/util/Collections.java
@@ -97,7 +97,7 @@ public class Collections {
       return size() == 0;
     }
 
-    public boolean contains(T e) {
+    public boolean contains(Object e) {
       synchronized (lock) { return collection.contains(e); }
     }
 
@@ -109,8 +109,8 @@ public class Collections {
       synchronized (lock) { return this.collection.addAll(collection); }
     }
 
-    public boolean remove(T e) {
-      synchronized (lock) { return collection.remove(e); }
+    public boolean remove(Object e) {
+      synchronized (lock) { return collection.remove((T)e); }
     }
 
     public <T> T[] toArray(T[] array) {
@@ -143,16 +143,16 @@ public class Collections {
     public void clear() {
       synchronized (lock) { map.clear(); }
     }
-    public boolean containsKey(K key) {
+    public boolean containsKey(Object key) {
       synchronized (lock) { return map.containsKey(key); }
     }
-    public boolean containsValue(V value) {
+    public boolean containsValue(Object value) {
       synchronized (lock) { return map.containsValue(value); }
     }
     public Set<java.util.Map.Entry<K, V>> entrySet() {
       synchronized (lock) { return new SynchronizedSet<java.util.Map.Entry<K, V>>(lock, map.entrySet()); }
     }
-    public V get(K key) {
+    public V get(Object key) {
       synchronized (lock) { return map.get(key); }
     }
     public boolean isEmpty() {
@@ -167,7 +167,7 @@ public class Collections {
     public void putAll(Map<? extends K, ? extends V> elts) {
       synchronized (lock) { map.putAll(elts); }
     }
-    public V remove(K key) {
+    public V remove(Object key) {
       synchronized (lock) { return map.remove(key); }
     }
     public int size() {
@@ -283,7 +283,7 @@ public class Collections {
       throw new UnsupportedOperationException("not supported");
     }
 
-    public boolean contains(T element) {
+    public boolean contains(Object element) {
       return inner.contains(element);
     }
 
@@ -295,7 +295,7 @@ public class Collections {
       return inner.iterator();
     }
 
-    public boolean remove(T element) {
+    public boolean remove(Object element) {
       throw new UnsupportedOperationException("not supported");
     }
 
diff --git a/classpath/java/util/HashMap.java b/classpath/java/util/HashMap.java
index 43ee2e8148..dd6eb85f61 100644
--- a/classpath/java/util/HashMap.java
+++ b/classpath/java/util/HashMap.java
@@ -107,7 +107,7 @@ public class HashMap<K, V> implements Map<K, V> {
     array = newArray;
   }
 
-  private Cell<K, V> find(K key) {
+  private Cell<K, V> find(Object key) {
     if (array != null) {
       int index = helper.hash(key) & (array.length - 1);
       for (Cell<K, V> c = array[index]; c != null; c = c.next()) {
@@ -158,20 +158,29 @@ public class HashMap<K, V> implements Map<K, V> {
     return c;
   }
 
-  public boolean containsKey(K key) {
+  public boolean containsKey(Object key) {
     return find(key) != null;
   }
 
-  public boolean containsValue(V value) {
-    return values().contains(value);
+  public boolean containsValue(Object value) {
+  	if (array != null) {
+      int index = array.length - 1;
+      for (Cell<K, V> c = array[index]; c != null; c = c.next()) {
+        if (helper.equal(value, c.getValue())) {
+          return true;
+        }
+      }
+    }  
+	
+		return false;
   }
 
-  public V get(K key) {
+  public V get(Object key) {
     Cell<K, V> c = find(key);
     return (c == null ? null : c.getValue());
   }
 
-  public Cell<K, V> removeCell(K key) {
+  public Cell<K, V> removeCell(Object key) {
     Cell<K, V> old = null;
     if (array != null) {
       int index = helper.hash(key) & (array.length - 1);
@@ -213,8 +222,8 @@ public class HashMap<K, V> implements Map<K, V> {
     }
   }
 
-  public V remove(K key) {
-    Cell<K, V> c = removeCell(key);
+  public V remove(Object key) {
+    Cell<K, V> c = removeCell((K)key);
     return (c == null ? null : c.getValue());
   }
 
@@ -314,8 +323,8 @@ public class HashMap<K, V> implements Map<K, V> {
       return HashMap.this.isEmpty();
     }
 
-    public boolean contains(Entry<K, V> e) {
-      return containsKey(e.getKey());
+    public boolean contains(Object o) {
+      return (o instanceof Entry<?,?>) ? containsKey(((Entry<?,?>)o).getKey()) : false;
     }
 
     public boolean add(Entry<K, V> e) {
@@ -328,6 +337,10 @@ public class HashMap<K, V> implements Map<K, V> {
       return change;
     }
 
+		public boolean remove(Object o) {
+			return (o instanceof Entry<?,?>) ? remove((Entry<?,?>)o) : false;
+		}
+
     public boolean remove(Entry<K, V> e) {
       return removeCell(e.getKey()) != null;
     }
@@ -354,7 +367,7 @@ public class HashMap<K, V> implements Map<K, V> {
       return HashMap.this.isEmpty();
     }
 
-    public boolean contains(K key) {
+    public boolean contains(Object key) {
       return containsKey(key);
     }
 
@@ -368,7 +381,7 @@ public class HashMap<K, V> implements Map<K, V> {
       return change;
     }
 
-    public boolean remove(K key) {
+    public boolean remove(Object key) {
       return removeCell(key) != null;
     }
 
@@ -395,7 +408,7 @@ public class HashMap<K, V> implements Map<K, V> {
       return HashMap.this.isEmpty();
     }
 
-    public boolean contains(V value) {
+    public boolean contains(Object value) {
       return containsValue(value);
     }
 
@@ -407,7 +420,7 @@ public class HashMap<K, V> implements Map<K, V> {
       throw new UnsupportedOperationException();      
     }
 
-    public boolean remove(V value) {
+    public boolean remove(Object value) {
       throw new UnsupportedOperationException();
     }
 
diff --git a/classpath/java/util/HashSet.java b/classpath/java/util/HashSet.java
index 6e6e96dd5d..b89c317a35 100644
--- a/classpath/java/util/HashSet.java
+++ b/classpath/java/util/HashSet.java
@@ -36,7 +36,7 @@ public class HashSet<T> implements Set<T> {
     return map.isEmpty();
   }
 
-  public boolean contains(T element) {
+  public boolean contains(Object element) {
     return map.containsKey(element);
   }
 
@@ -50,7 +50,7 @@ public class HashSet<T> implements Set<T> {
     return change;
   }
 
-  public boolean remove(T element) {
+  public boolean remove(Object element) {
     return map.remove(element) != Value;
   }
 
diff --git a/classpath/java/util/Hashtable.java b/classpath/java/util/Hashtable.java
index 8ae75941a3..978847a6b7 100644
--- a/classpath/java/util/Hashtable.java
+++ b/classpath/java/util/Hashtable.java
@@ -40,15 +40,15 @@ public class Hashtable<K, V> implements Map<K, V> {
     return map.size();
   }
 
-  public synchronized boolean containsKey(K key) {
+  public synchronized boolean containsKey(Object key) {
     return map.containsKey(key);
   }
 
-  public synchronized boolean containsValue(V value) {
+  public synchronized boolean containsValue(Object value) {
     return map.containsValue(value);
   }
 
-  public synchronized V get(K key) {
+  public synchronized V get(Object key) {
     return map.get(key);
   }
 
@@ -60,7 +60,7 @@ public class Hashtable<K, V> implements Map<K, V> {
     map.putAll(elts);
   }
 
-  public synchronized V remove(K key) {
+  public synchronized V remove(Object key) {
     return map.remove(key);
   }
 
diff --git a/classpath/java/util/IdentityHashMap.java b/classpath/java/util/IdentityHashMap.java
index 7a86c5a192..ce6f34cbe9 100644
--- a/classpath/java/util/IdentityHashMap.java
+++ b/classpath/java/util/IdentityHashMap.java
@@ -29,15 +29,15 @@ public class IdentityHashMap<K, V> implements Map<K, V> {
     return map.size();
   }
 
-  public boolean containsKey(K key) {
+  public boolean containsKey(Object key) {
     return map.containsKey(key);
   }
 
-  public boolean containsValue(V value) {
+  public boolean containsValue(Object value) {
     return map.containsValue(value);
   }
 
-  public V get(K key) {
+  public V get(Object key) {
     return map.get(key);
   }
 
@@ -49,7 +49,7 @@ public class IdentityHashMap<K, V> implements Map<K, V> {
     map.putAll(elts);
   }
 
-  public V remove(K key) {
+  public V remove(Object key) {
     return map.remove(key);
   }
 
diff --git a/classpath/java/util/LinkedList.java b/classpath/java/util/LinkedList.java
index a9f4c442ce..657d245997 100644
--- a/classpath/java/util/LinkedList.java
+++ b/classpath/java/util/LinkedList.java
@@ -60,7 +60,7 @@ public class LinkedList<T> implements List<T> {
     }
   }
   
-  private Cell<T> find(T element) {
+  private Cell<T> find(Object element) {
     for (Cell<T> c = front; c != null; c = c.next) {
       if (equal(c.value, element)) {
         return c;
@@ -93,7 +93,7 @@ public class LinkedList<T> implements List<T> {
     return size;
   }
 
-  public boolean contains(T element) {
+  public boolean contains(Object element) {
     return find(element) != null;
   }
 
@@ -186,7 +186,7 @@ public class LinkedList<T> implements List<T> {
     }
   }
 
-  public boolean remove(T element) {
+  public boolean remove(Object element) {
     Cell<T> c = find(element);
     if (c == null) {
       return false;
diff --git a/classpath/java/util/Map.java b/classpath/java/util/Map.java
index 0b5fa550b2..47edee351e 100644
--- a/classpath/java/util/Map.java
+++ b/classpath/java/util/Map.java
@@ -15,17 +15,17 @@ public interface Map<K, V> {
 
   public int size();
 
-  public boolean containsKey(K key);
+  public boolean containsKey(Object obj);
 
-  public boolean containsValue(V value);
+  public boolean containsValue(Object obj);
 
-  public V get(K key);
+  public V get(Object key);
 
   public V put(K key, V value);
 
   public void putAll(Map<? extends K,? extends V> elts);
 
-  public V remove(K key);
+  public V remove(Object key);
 
   public void clear();
 
diff --git a/classpath/java/util/TreeSet.java b/classpath/java/util/TreeSet.java
index eaff92106a..4940eb0d22 100644
--- a/classpath/java/util/TreeSet.java
+++ b/classpath/java/util/TreeSet.java
@@ -60,7 +60,7 @@ public class TreeSet<T>  extends AbstractSet<T> implements Collection<T> {
     }
   }
     
-  public boolean remove(T value) {
+  public boolean remove(Object value) {
     PersistentSet.Path<Cell<T>> p = set.find(new Cell(value, null));
     if (p.fresh()) {
       return false;
@@ -85,7 +85,7 @@ public class TreeSet<T>  extends AbstractSet<T> implements Collection<T> {
     return size == 0;
   }
 
-  public boolean contains(T value) {
+  public boolean contains(Object value) {
     return !set.find(new Cell(value, null)).fresh();
   }
 
diff --git a/classpath/java/util/Vector.java b/classpath/java/util/Vector.java
index 21bd896b7c..f06f58ecbc 100644
--- a/classpath/java/util/Vector.java
+++ b/classpath/java/util/Vector.java
@@ -29,7 +29,7 @@ public class Vector<T> implements List<T> {
     return list.size();
   }
 
-  public synchronized boolean contains(T element) {
+  public synchronized boolean contains(Object element) {
     return list.contains(element);
   }
 
@@ -85,7 +85,7 @@ public class Vector<T> implements List<T> {
     remove(index);
   }
 
-  public synchronized boolean remove(T element) {
+  public synchronized boolean remove(Object element) {
     return list.remove(element);
   }
 
diff --git a/classpath/java/util/WeakHashMap.java b/classpath/java/util/WeakHashMap.java
index 1618d58907..2dc5c9fceb 100644
--- a/classpath/java/util/WeakHashMap.java
+++ b/classpath/java/util/WeakHashMap.java
@@ -44,17 +44,17 @@ public class WeakHashMap<K, V> implements Map<K, V> {
     return map.size();
   }
 
-  public boolean containsKey(K key) {
+  public boolean containsKey(Object key) {
     poll();
     return map.containsKey(key);
   }
 
-  public boolean containsValue(V value) {
+  public boolean containsValue(Object  value) {
     poll();
     return map.containsValue(value);
   }
 
-  public V get(K key) {
+  public V get(Object key) {
     poll();
     return map.get(key);
   }
@@ -68,7 +68,7 @@ public class WeakHashMap<K, V> implements Map<K, V> {
     map.putAll(elts);
   }
 
-  public V remove(K key) {
+  public V remove(Object key) {
     poll();
     return map.remove(key);
   }
diff --git a/makefile b/makefile
index 1159306512..98694b3d1c 100644
--- a/makefile
+++ b/makefile
@@ -334,6 +334,13 @@ test: build
 		$(executable) $(mode) "$(flags)" \
 		$(call class-names,$(test-build),$(test-classes))
 
+.PHONY: tarball
+tarball:
+	@echo "creating build/avian-$(version).tar.bz2"
+	@mkdir -p build
+	(cd .. && tar --exclude=build --exclude='.*' --exclude='*~' -cjf \
+		avian/build/avian-$(version).tar.bz2 avian)
+
 .PHONY: javadoc
 javadoc:
 	javadoc -sourcepath classpath -d build/javadoc -subpackages java \