read the javadocs on wait(long) to see why this change was made

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@590990 13f79535-47bb-0310-9956-ffa450edef68

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);
         }
     }