Loading a pack200 JAR with JarURLConnection.getJarFile() leads to IOException

FULL PRODUCT VERSION :
java version " 1.7.0_21 "
Java(TM) SE Runtime Environment (build 1.7.0_21-b11)
Java HotSpot(TM) Client VM (build 23.21-b01, mixed mode, sharing)

This also occurs with Java 1.7.0_17.

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601], also occurs on OS X 10.8.3 and other Windows versions. Not tested on linux.

A DESCRIPTION OF THE PROBLEM :
When loading an additional JAR from an applet with -Djnlp.packEnabled=true by using JarUrlConnection.getJarFile() an " java.io.IOException: Invalid jar file " is thrown.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Create a JAR from the test case (testapplet.jar)
2. Sign and pack200 the JAR (testapplet.jar.pack.gz)
3. Create a copy of the normal and pack200 version of the JAR and name them " additional.jar " and " additional.jar.pack.gz "
4. Create HTML file to load the applet by using the testapplet.jar(.pack.gz) file. All JAR files should be on the same directory (code base).
5 Open the HTML in a browser, set trace level to 5.

OR use the test case at:

http://www.realobjects.com/fileadmin/products/testapplet/oracle-bug2/pack200.html

For IE
http://www.realobjects.com/fileadmin/products/testapplet/oracle-bug2/pack200-ie.html

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
No exception, JAR can be loaded and accessed
ACTUAL -
Exception, JAR is not loaded correctly

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Java Plug-in 10.21.2.11
Using JRE version 1.7.0_21-b11 Java HotSpot(TM) Client VM
User home directory = C:\Users\sebastian.giffhorn
----------------------------------------------------
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to <n>
----------------------------------------------------
basic: Starting applet teardown
basic: Finished applet teardown
basic: PluginMain.unregisterApplet: 1 from mananger sun.plugin2.applet.Applet2Manager@a21ac2
basic: Removed progress listener: sun.plugin.util.ProgressMonitorAdapter@11cc36
security: --- parseCommandLine converted : -Xmx256m -Djnlp.packEnabled=true
into:
[-Xmx256m, -Djnlp.packEnabled=true]
basic: Added progress listener: sun.plugin.util.ProgressMonitorAdapter@aafcb8
basic: Plugin2ClassLoader.addURL parent called for http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/testapplet.jar
security: Validate the certificate chain using CertPath API
security: SHA-256 finger print: 6BE7B7BB9E9DBCC0E168FC768727256F0DD54D97FF09172E3B592AE3347CE0D5
security: SHA-256 finger print: AF840CA2B9DFB776BF81AA94C401BC440C52E5C590C43607A13D6680D83E3349
security: SHA-256 finger print: 8D722F81A9C113C0791DF136A2966DB26C950A971DB46B4199F4EA54B78BFB9F
security: The certificate hasnt been expired, no need to check timestamping info
security: The CRL support is disabled
security: The OCSP support is disabled
security: This OCSP End Entity validation is disabled
network: Created version ID: 1.7.0.21
network: Created version ID: 1.7.0.21
basic: Applet loaded.
basic: Applet resized and added to parent container
basic: PERF: AppletExecutionRunnable - applet.init() BEGIN ; jvmLaunch dt 325625 us, pluginInit dt 19861476 us, TotalTime: 20187101 us
***** Before getJarFile
network: Connecting http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar.pack.gz with proxy=DIRECT
network: Connecting http://sgmac:80/ with proxy=DIRECT
network: Connecting http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar.pack.gz with proxy=DIRECT
network: Connecting http://sgmac:80/ with proxy=DIRECT
network: ResponseCode for http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar.pack.gz : 200
network: Encoding for http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar.pack.gz : null
network: Server response: (length: 5052, lastModified: Mon May 06 15:40:37 CEST 2013, downloadVersion: null, mimeType: application/x-gzip)
network: Downloading resource: http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar.pack.gz
Content-Length: 5.052
Content-Encoding: pack200-gzip
network: Disconnect connection to http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar.pack.gz
java.io.IOException: Invalid jar file
at com.sun.deploy.net.HttpDownloadHelper.download(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResourceToTempDir(Unknown Source)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at sun.plugin.PluginURLJarFileCallBack$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin.PluginURLJarFileCallBack.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(Unknown Source)
at sun.net.www.protocol.jar.JarFileFactory.get(Unknown Source)
at sun.net.www.protocol.jar.JarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFileInternal(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)
at TestApplet.init(Unknown Source)
at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.init(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
com.sun.deploy.net.FailedDownloadException: Unable to load resource: http://sgmac/workspaces/eclipse/Pack200%20Applet-LoadJAR/additional.jar
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at sun.plugin.PluginURLJarFileCallBack$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin.PluginURLJarFileCallBack.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(Unknown Source)
at sun.net.www.protocol.jar.JarFileFactory.get(Unknown Source)
at sun.net.www.protocol.jar.JarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFileInternal(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)
at TestApplet.init(Unknown Source)
at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.init(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by:
java.io.IOException: Invalid jar file
at com.sun.deploy.net.HttpDownloadHelper.download(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResourceToTempDir(Unknown Source)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine.downloadResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at sun.plugin.PluginURLJarFileCallBack$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin.PluginURLJarFileCallBack.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(Unknown Source)
at sun.net.www.protocol.jar.JarFileFactory.get(Unknown Source)
at sun.net.www.protocol.jar.JarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFileInternal(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)
at TestApplet.init(Unknown Source)
at com.sun.deploy.uitoolkit.impl.awt.AWTAppletAdapter.init(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
basic: Applet initialized
basic: Starting applet
basic: completed perf rollup
basic: Applet made visible
basic: Applet started
basic: Told clients applet is started


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.net.JarURLConnection;
import java.net.URL;
import java.util.jar.JarFile;

import javax.swing.JApplet;

public class TestApplet extends JApplet {
    
    
    public void init() {
        try {
            JarURLConnection uc = null;
            URL url = null;
            url = new URL(getCodeBase(), " additional.jar " );
            url = new URL( " jar " , " " , url + " !/ " );
            uc = (JarURLConnection) url.openConnection();
            System.out.println( " ***** Before getJarFile " );
            JarFile jf = uc.getJarFile();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

---------- END SOURCE ----------