diff --git a/src/clj/clojure/core.clj b/src/clj/clojure/core.clj
index 9738ab8..b3faaf3 100644
--- a/src/clj/clojure/core.clj
+++ b/src/clj/clojure/core.clj
@@ -2103,10 +2103,10 @@
   the value that was swapped in."
   {:added "1.0"
    :static true}
-  ([^clojure.lang.Atom atom f] (.swap atom f))
-  ([^clojure.lang.Atom atom f x] (.swap atom f x))
-  ([^clojure.lang.Atom atom f x y] (.swap atom f x y))
-  ([^clojure.lang.Atom atom f x y & args] (.swap atom f x y args)))
+  ([^clojure.lang.IAtom atom f] (.swap atom f))
+  ([^clojure.lang.IAtom atom f x] (.swap atom f x))
+  ([^clojure.lang.IAtom atom f x y] (.swap atom f x y))
+  ([^clojure.lang.IAtom atom f x y & args] (.swap atom f x y args)))
 
 (defn compare-and-set!
   "Atomically sets the value of atom to newval if and only if the
@@ -2114,14 +2114,14 @@
   set happened, else false"
   {:added "1.0"
    :static true}
-  [^clojure.lang.Atom atom oldval newval] (.compareAndSet atom oldval newval))
+  [^clojure.lang.IAtom atom oldval newval] (.compareAndSet atom oldval newval))
 
 (defn reset!
   "Sets the value of atom to newval without regard for the
   current value. Returns newval."
   {:added "1.0"
    :static true}
-  [^clojure.lang.Atom atom newval] (.reset atom newval))
+  [^clojure.lang.IAtom atom newval] (.reset atom newval))
 
 (defn set-validator!
   "Sets the validator-fn for a var/ref/agent/atom. validator-fn must be nil or a
diff --git a/src/jvm/clojure/lang/Atom.java b/src/jvm/clojure/lang/Atom.java
index 5033d13..a964c49 100644
--- a/src/jvm/clojure/lang/Atom.java
+++ b/src/jvm/clojure/lang/Atom.java
@@ -14,7 +14,7 @@ package clojure.lang;
 
 import java.util.concurrent.atomic.AtomicReference;
 
-final public class Atom extends ARef{
+final public class Atom extends ARef implements IAtom{
 final AtomicReference state;
 
 public Atom(Object state){
diff --git a/src/jvm/clojure/lang/IAtom.java b/src/jvm/clojure/lang/IAtom.java
new file mode 100644
index 0000000..74908f0
--- /dev/null
+++ b/src/jvm/clojure/lang/IAtom.java
@@ -0,0 +1,27 @@
+/**
+ *   Copyright (c) Rich Hickey. All rights reserved.
+ *   The use and distribution terms for this software are covered by the
+ *   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
+ *   which can be found in the file epl-v10.html at the root of this distribution.
+ *   By using this software in any fashion, you are agreeing to be bound by
+ * 	 the terms of this license.
+ *   You must not remove this notice, or any other, from this software.
+ **/
+
+/* rich Aug 2, 2009 */
+
+package clojure.lang;
+
+public interface IAtom{
+Object swap(IFn f);
+
+Object swap(IFn f, Object arg);
+
+Object swap(IFn f, Object arg1, Object arg2);
+
+Object swap(IFn f, Object x, Object y, ISeq args);
+
+boolean compareAndSet(Object oldv, Object newv);
+
+Object reset(Object newval);
+}