diff --git a/rxjava-core/src/main/java/rx/operators/ChunkedOperation.java b/rxjava-core/src/main/java/rx/operators/ChunkedOperation.java
index 5cd0845ea5..d68501d122 100644
--- a/rxjava-core/src/main/java/rx/operators/ChunkedOperation.java
+++ b/rxjava-core/src/main/java/rx/operators/ChunkedOperation.java
@@ -187,8 +187,11 @@ public void emitChunk(Chunk<T, C> chunk) {
                 return;
             }
 
-            subscription.unsubscribe();
+            // Fixed issue 428.
+            // As unsubscribe will cancel the Future, and the currrent thread's interrupt status
+            // will be set. So we need to emit the chunk before unsubscribe.
             super.emitChunk(chunk);
+            subscription.unsubscribe();
             createChunk();
         }
 
diff --git a/rxjava-core/src/main/java/rx/operators/OperationBuffer.java b/rxjava-core/src/main/java/rx/operators/OperationBuffer.java
index 1cc559fb57..898260d0ef 100644
--- a/rxjava-core/src/main/java/rx/operators/OperationBuffer.java
+++ b/rxjava-core/src/main/java/rx/operators/OperationBuffer.java
@@ -15,8 +15,11 @@
  */
 package rx.operators;
 
+import static org.junit.Assert.assertFalse;
+
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 
 import org.junit.Before;
@@ -37,6 +40,7 @@
 import rx.util.Opening;
 import rx.util.Openings;
 import rx.util.functions.Action0;
+import rx.util.functions.Action1;
 import rx.util.functions.Func0;
 import rx.util.functions.Func1;
 
@@ -631,6 +635,40 @@ public Subscription onSubscribe(Observer<? super Closing> observer) {
             inOrder.verify(observer, Mockito.times(1)).onCompleted();
         }
 
+        @Test
+        public void testLongTimeAction() throws InterruptedException {
+            final CountDownLatch latch = new CountDownLatch(1);
+            LongTimeAction action = new LongTimeAction(latch);
+            Observable.from(1).buffer(10, TimeUnit.MILLISECONDS, 10)
+                    .subscribe(action);
+            latch.await();
+            assertFalse(action.fail);
+        }
+
+        private static class LongTimeAction implements Action1<List<Integer>> {
+
+            CountDownLatch latch;
+            boolean fail = false;
+
+            public LongTimeAction(CountDownLatch latch) {
+                this.latch = latch;
+            }
+
+            @Override
+            public void call(List<Integer> t1) {
+                try {
+                    if (fail) {
+                        return;
+                    }
+                    Thread.sleep(200);
+                } catch (InterruptedException e) {
+                    fail = true;
+                } finally {
+                    latch.countDown();
+                }
+            }
+        }
+
         private List<String> list(String... args) {
             List<String> list = new ArrayList<String>();
             for (String arg : args) {