That's what the stack trace says. I've used both 7zip and kzip (didn't end up more than 5 bytes different.) Here's the stack trace from the Java console:
ava.util.zip.ZipException: Not in GZIP format
at java.util.zip.GZIPInputStream.readHeader(Unknown Source)
at java.util.zip.GZIPInputStream.<init>(Unknown Source)
at java.util.zip.GZIPInputStream.<init>(Unknown Source)
at com.sun.deploy.net.HttpDownloadHelper.download(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToTempFile(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToCache(Unknown Source)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine._downloadCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResourceCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResourceCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at sun.plugin.PluginURLJarFileCallBack$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin.PluginURLJarFileCallBack.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(Unknown Source)
at sun.net.www.protocol.jar.JarFileFactory.get(Unknown Source)
at sun.net.www.protocol.jar.JarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFileInternal(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.getJarFile(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.access$1000(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.ensureOpen(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.<init>(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath.getResource(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader$2.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin2.applet.Plugin2ClassLoader.findClassHelper(Unknown Source)
at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Unknown Source)
at sun.plugin2.applet.Plugin2Manager.initAppletAdapter(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
com.sun.deploy.net.FailedDownloadException: Unable to load resource:
http://java4k.com/applet.php?gid=471 at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine._downloadCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResourceCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResourceCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at sun.plugin.PluginURLJarFileCallBack$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin.PluginURLJarFileCallBack.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(Unknown Source)
at sun.net.www.protocol.jar.JarFileFactory.get(Unknown Source)
at sun.net.www.protocol.jar.JarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFileInternal(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.getJarFile(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.access$1000(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.ensureOpen(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.<init>(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath.getResource(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader$2.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin2.applet.Plugin2ClassLoader.findClassHelper(Unknown Source)
at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Unknown Source)
at sun.plugin2.applet.Plugin2Manager.initAppletAdapter(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by:
java.util.zip.ZipException: Not in GZIP format
at java.util.zip.GZIPInputStream.readHeader(Unknown Source)
at java.util.zip.GZIPInputStream.<init>(Unknown Source)
at java.util.zip.GZIPInputStream.<init>(Unknown Source)
at com.sun.deploy.net.HttpDownloadHelper.download(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToTempFile(Unknown Source)
at com.sun.deploy.cache.Cache.downloadResourceToCache(Unknown Source)
at com.sun.deploy.net.DownloadEngine.actionDownload(Unknown Source)
at com.sun.deploy.net.DownloadEngine._downloadCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResourceCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResourceCacheEntry(Unknown Source)
at com.sun.deploy.cache.ResourceProviderImpl.getResource(Unknown Source)
at sun.plugin.PluginURLJarFileCallBack$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin.PluginURLJarFileCallBack.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.retrieve(Unknown Source)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(Unknown Source)
at sun.net.www.protocol.jar.JarFileFactory.get(Unknown Source)
at sun.net.www.protocol.jar.JarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.connect(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFileInternal(Unknown Source)
at sun.plugin.net.protocol.jar.CachedJarURLConnection.getJarFile(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.getJarFile(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.access$1000(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.ensureOpen(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$JarLoader.<init>(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
at com.sun.deploy.security.DeployURLClassPath.getResource(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader$2.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.plugin2.applet.Plugin2ClassLoader.findClassHelper(Unknown Source)
at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Unknown Source)
at sun.plugin2.applet.Plugin2Manager.initAppletAdapter(Unknown Source)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)