diff --git a/src/java/com/samskivert/swing/RuntimeAdjust.java b/src/java/com/samskivert/swing/RuntimeAdjust.java
index 687ab66c..5743b760 100644
--- a/src/java/com/samskivert/swing/RuntimeAdjust.java
+++ b/src/java/com/samskivert/swing/RuntimeAdjust.java
@@ -503,7 +503,7 @@ public class RuntimeAdjust
 
         @Override public boolean equals (Object other)
         {
-            return _name.equals(((Adjust)other)._name);
+            return (other instanceof Adjust) && _name.equals(((Adjust)other)._name);
         }
 
         @Override public int hashCode ()
diff --git a/src/java/com/samskivert/util/ConfigUtil.java b/src/java/com/samskivert/util/ConfigUtil.java
index 8ce608f6..9b556577 100644
--- a/src/java/com/samskivert/util/ConfigUtil.java
+++ b/src/java/com/samskivert/util/ConfigUtil.java
@@ -585,7 +585,7 @@ public class ConfigUtil
         }
 
         @Override public boolean equals (Object other) {
-            return _package.equals(((PropRecord)other)._package);
+            return (other instanceof PropRecord) && _package.equals(((PropRecord)other)._package);
         }
 
         @Override public String toString () {
diff --git a/src/java/com/samskivert/util/KeyValue.java b/src/java/com/samskivert/util/KeyValue.java
index f67b6fe2..3d912446 100644
--- a/src/java/com/samskivert/util/KeyValue.java
+++ b/src/java/com/samskivert/util/KeyValue.java
@@ -63,10 +63,10 @@ public class KeyValue<K extends Comparable<? super K>,V>
     }
 
     @Override
-    @SuppressWarnings("unchecked") // documentation inherited
+    @SuppressWarnings("unchecked")
     public boolean equals (Object other)
     {
-        return key.equals(((KeyValue<K,V>)other).key);
+        return (other instanceof KeyValue<?,?>) && key.equals(((KeyValue<K,V>)other).key);
     }
 
     @Override
@@ -75,7 +75,7 @@ public class KeyValue<K extends Comparable<? super K>,V>
         return key.hashCode();
     }
 
-    // documentation inherited
+    // from interface Comparable<KeyValue<K,V>>
     public int compareTo (KeyValue<K,V> other)
     {
         return key.compareTo(other.key);