--- src/org/jmock/lib/concurrent/DeterministicScheduler.java	2008-06-23 14:06:51.000000000 +0200
+++ src/org/jmock/lib/concurrent/DeterministicScheduler.java-gil	2011-07-27 20:46:08.446224533 +0200
@@ -110,21 +110,21 @@
         throw blockingOperationsNotSupported();
     }
 
-    public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks) throws InterruptedException {
+    public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks) throws InterruptedException {
         throw blockingOperationsNotSupported();
     }
 
-    public <T> List<Future<T>> invokeAll(Collection<Callable<T>> tasks, long timeout, TimeUnit unit) throws InterruptedException {
+    public <T> List<Future<T>> invokeAll(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit) throws InterruptedException {
         throw blockingOperationsNotSupported();
     }
     
-    public <T> T invokeAny(Collection<Callable<T>> tasks)
+    public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
         throws InterruptedException, ExecutionException 
     {
         throw blockingOperationsNotSupported();
     }
 
-    public <T> T invokeAny(Collection<Callable<T>> tasks, long timeout, TimeUnit unit) 
+    public <T> T invokeAny(Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)
         throws InterruptedException, ExecutionException, TimeoutException 
     {
         throw blockingOperationsNotSupported();