diff --git a/akka-core/src/main/scala/dispatch/ThreadPoolBuilder.scala b/akka-core/src/main/scala/dispatch/ThreadPoolBuilder.scala
index 55755250e2..6f8da64073 100644
--- a/akka-core/src/main/scala/dispatch/ThreadPoolBuilder.scala
+++ b/akka-core/src/main/scala/dispatch/ThreadPoolBuilder.scala
@@ -34,6 +34,7 @@ trait ThreadPoolBuilder {
   def buildThreadPool(): Unit = synchronized {
     ensureNotActive
     inProcessOfBuilding = false
+    threadPoolBuilder.allowCoreThreadTimeOut(true)
     if (boundedExecutorBound > 0) {
       val boundedExecutor = new BoundedExecutorDecorator(threadPoolBuilder, boundedExecutorBound)
       boundedExecutorBound = -1