Bundle: j2sdk-1_5_0-beta-bin-b24-windows-i586-15_oct_2003.exe
Platform: Windows Server 2003, SE
Test case: http://sekai.sfbay/projects3/java_websvcs_j2se_1.5_tiger_l10n/java_websvcs_j2se_1.5_tiger_l10n/web/test_cases/jws/opt-out_jws_testcases.html#3

The following exception occurred during autodownload.
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java.io.IOException
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at com.sun.javaws.net.BasicNetworkLayer.doRequest(Unknown Source)
at com.sun.javaws.net.BasicNetworkLayer.doGetRequest(Unknown Source)
at com.sun.javaws.cache.DownloadProtocol.doDownload(Unknown Source)
at com.sun.javaws.cache.DownloadProtocol.getResource(Unknown Source)
at com.sun.javaws.LaunchDownload.downloadJarFiles(Unknown Source)
at com.sun.javaws.LaunchDownload.downloadEagerorAll(Unknown Source)
at com.sun.javaws.Launcher.downloadResources(Unknown Source)
at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
at com.sun.javaws.Launcher.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.io.IOException: Server returned HTTP response code: 500 for URL: http://java.sun.com/webapps/jawsautodl/AutoDL/j2se/javaws-1_0_1-j2re-1_4_1-inst-windows-i586-i.jar
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at java.net.HttpURLConnection.getResponseCode(Unknown Source)
... 11 more

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And also, it changes the behavior using Windows XP as follows.
JNLPException occurred.
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JNLPException[category: ïNô«âtâ@âCâïâGâëü[ : Exception: null : LaunchDesc:
<jnlp spec="1.0+" codebase="http://java.sun.com/webapps/jawsautodl/AutoDL/j2se/">
  <information>
    <title>J2RE 1.4.1 Installer (I)</title>
    <vendor>Sun Microsystems, Inc.</vendor>
    <homepage href="null"/>
  </information>
  <security>
    <all-permissions/>
  </security>
  <resources>
    <j2se href="http://java.sun.com/products/autodl/j2se" version="1.3+"/>
    <jar href="http://java.sun.com/webapps/jawsautodl/AutoDL/j2se/javaws-1_0_1-j2re-1_4_1-inst-windows-i586-i.jar" download="eager" main="false"/>
    <jar href="http://java.sun.com/webapps/jawsautodl/AutoDL/j2se/javaws-1_0_1-j2re-1_4_1-data-windows-i586-i.jar" download="lazy" main="false"/>
    <property name="javaVersion" value="1.4.1"/>
    <property name="platformVersion" value="1.4"/>
    <property name="installerLocation" value="javaws-1_0_1-j2re-1_4_1-data-windows-i586-i.jar"/>
    <property name="installerEntry" value="jre.dat"/>
    <property name="licenseEntry" value="LICENSE"/>
    <property name="lib" value="j2re-installer"/>
    <property name="msvcrt.versionMS" value="60000"/>
    <property name="msvcrt.versionLS" value="20910000"/>
    <property name="execString" value="{0} -s -a -s -f1{1}"/>
    <property name="javaPath" value="bin\\javaw.exe"/>
    <property name="verbose" value="true"/>
    <property name="hopper" value="true"/>
    <property name="isWindowsInstall" value="true"/>
    <jar href="http://java.sun.com/webapps/jawsautodl/AutoDL/j2se/javaws-1_0_1-j2re-1_4_1-native-windows-i586-i.jar" download="eager" main="false"/>
  </resources>
  <installer-desc main-class="com.sun.webstart.installers.Main"/>
</jnlp> ]
at com.sun.javaws.Launcher.executeInstallers(Unknown Source)
at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
at com.sun.javaws.Launcher.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
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