diff --git a/src/main/org/apache/tools/ant/util/WorkerAnt.java b/src/main/org/apache/tools/ant/util/WorkerAnt.java
index 919cf4641..725a72a2d 100644
--- a/src/main/org/apache/tools/ant/util/WorkerAnt.java
+++ b/src/main/org/apache/tools/ant/util/WorkerAnt.java
@@ -114,10 +114,9 @@ public class WorkerAnt extends Thread {
      */
     public void waitUntilFinished(long timeout) throws InterruptedException {
         synchronized(notify) {
-            if(finished) {
-                return;
+            while (!finished) {
+                notify.wait(timeout);
             }
-            notify.wait(timeout);
         }
     }