diff --git a/src/testcases/org/apache/tools/ant/taskdefs/JarTest.java b/src/testcases/org/apache/tools/ant/taskdefs/JarTest.java
index 45455ae88..968433d11 100644
--- a/src/testcases/org/apache/tools/ant/taskdefs/JarTest.java
+++ b/src/testcases/org/apache/tools/ant/taskdefs/JarTest.java
@@ -30,6 +30,7 @@ import java.util.zip.ZipEntry;
 import java.util.zip.ZipFile;
 import org.apache.tools.ant.BuildFileTest;
 import org.apache.tools.ant.taskdefs.condition.Os;
+import org.apache.tools.ant.util.FileUtils;
 
 /**
  * @author Erik Meade <emeade@geekfarm.org>
@@ -124,10 +125,8 @@ public class JarTest extends BuildFileTest {
 
     private void testRecreate(String firstTarget, String secondTarget) {
         executeTarget(firstTarget);
-        int sleeptime = 2500;
-        if (Os.isFamily("windows")) {
-            sleeptime += 2500;
-        }
+        long sleeptime = 3000
+            + FileUtils.newFileUtils().getFileTimestampGranularity();
         try {
             Thread.currentThread().sleep(sleeptime);
         } catch (InterruptedException e) {