Incremental Update Test Case Failed (Build 11)

For the newly developed incremental update test case:

http://comanche.eng.sun.com/jawstest/update/

- The test case failed on Windows OS, but succeeded on Linux / Solaris
  Sparc. i.e., after you launch version 1.0, then you launch version 2.0,
  2.1, the application could be launched correctly. (The background
  update is working.)

  The following is the error on windows OS:

An error occurred while launching/running the application.

Title: Java Web Start JarDiff Test
Vendor: Sun Microsystems, Inc.
Category: Download Error

Unable to apply incremental update for resource: (http://comanche.eng.sun.com/servlets/JarDiffServer/update/javawsApp.jar, 2.0)

JNLPException[category: Download Error : Exception: java.util.zip.ZipException: error in opening zip file : LaunchDesc: null ]
at com.sun.javaws.cache.DownloadProtocol.applyPatch(DownloadProtocol.java:633)
at com.sun.javaws.cache.DownloadProtocol.access$1(DownloadProtocol.java:607)
at com.sun.javaws.cache.DownloadProtocol$RetrieveAction.actionDownload(DownloadProtocol.java:437)
at com.sun.javaws.cache.DownloadProtocol.doDownload(DownloadProtocol.java:593)
at com.sun.javaws.cache.DownloadProtocol.getResource(DownloadProtocol.java:746)
at com.sun.javaws.LaunchDownload.downloadJarFiles(LaunchDownload.java:556)
at com.sun.javaws.LaunchDownload.downloadEagerorAll(LaunchDownload.java:462)
at com.sun.javaws.Launcher.downloadResources(Launcher.java:595)
at com.sun.javaws.Launcher.handleApplicationDesc(Launcher.java:257)
at com.sun.javaws.Launcher.handleLaunchFile(Launcher.java:151)
at com.sun.javaws.Launcher.<init>(Launcher.java:113)
at com.sun.javaws.Main.main(Main.java:149)