This is from a customer escalation 1-17001929, case 65016052.

Comparing the source base for 5.0u5 and 5.0u6, the following lines seems to be
removed from 5.0u6, which might be the cause of this issue:

http://cheesypoof.uk.sun.com/lxr2/source/ws/deploy/src/common/share/classes/com/sun/deploy/resources/Deployment.java?v=Java_1.5.0_05

109	{ "security.dialog.buttonYes", "Yes" },
110	{ "security.dialog.buttonYes.acceleratorKey", new Integer(KeyEvent.VK_Y)},
111	{ "security.dialog.buttonNo", "No" },
112	{ "security.dialog.buttonNo.acceleratorKey", new Integer(KeyEvent.VK_N)},

---------------------------------------------------------------------------------

There appears to be a bug in 1.5.0_06 with respect to executing signed JARs. As 
part of installation of one of our products, a signed JAR is employed. Under 1.5
.0_06, we see the following errors in the Java Console:

network: Connecting http://w1k41sp3i4/lib/ImportIzmComJni.jar with proxy=DIRECT
network: Connecting http://w1k41sp3i4/lib/ImportIzmComJni.jar with cookie "WebLo
gicSession=RGJKwE4jv5HxIMaaiBiTC02So0o7V8JB1TZQudrJmio2qdGvPpS1|-247829476124952
3153/183364965/6/80/80/443/443/80/-1"
extensions: Installing optional package Extension : title(null), name(Jacozoom),
 spec vendor(null), spec version(null), impl vendor(null), impl vendor id(null),
 impl version(null), impl url(http://w1k41sp3i4/lib/izmcomjni.jar)
java.util.MissingResourceException: Can't find resource for bundle com.sun.deplo
y.resources.Deployment, key security.dialog.buttonYes.acceleratorKey
        at java.util.ResourceBundle.getObject(Unknown Source)
        at com.sun.deploy.resources.ResourceManager.getAcceleratorKey(Unknown So
urce)
        at com.sun.deploy.util.DialogFactory.showDownloadDialogImpl(Unknown Sour
ce)
        at com.sun.deploy.util.DialogFactory.access$200(Unknown Source)
        at com.sun.deploy.util.DialogFactory$4.execute(Unknown Source)
        at sun.plugin.util.PluginSysUtil$SysExecutionThread.run(Unknown Source)
extensions: Optional package download not granted by user
sun.misc.ExtensionInstallationException: User denied installation of http://w1k4
1sp3i4/lib/izmcomjni.jar
        at sun.plugin.extension.ExtensionInstallationImpl$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.plugin.extension.ExtensionInstallationImpl.installExtension(Unkno
wn Source)
        at sun.misc.ExtensionDependency.installExtension(Unknown Source)
        at sun.misc.ExtensionDependency.checkExtension(Unknown Source)
        at sun.misc.ExtensionDependency.checkExtensions(Unknown Source)
        at sun.misc.ExtensionDependency.checkExtensionsDependencies(Unknown Sour
ce)
        at sun.misc.URLClassPath$JarLoader.parseExtensionsDependencies(Unknown S
ource)
        at sun.misc.URLClassPath$JarLoader.getClassPath(Unknown Source)
        at sun.misc.URLClassPath.getLoader(Unknown Source)
        at sun.misc.URLClassPath.getResource(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at sun.applet.AppletClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.applet.AppletClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.applet.AppletClassLoader.loadCode(Unknown Source)
        at sun.applet.AppletPanel.createApplet(Unknown Source)
        at sun.plugin.AppletViewer.createApplet(Unknown Source)
        at sun.applet.AppletPanel.runLoader(Unknown Source)
        at sun.applet.AppletPanel.run(Unknown Source)
        at java.lang.Thread.run(Unknown Source)
basic: Modality pushed
basic: Modality popped
basic: Modality pushed
basic: Modality popped
extensions: Optional package installation failed.

This issue appears to have been reported on the Sun Java forums:
http://forums.java.sun.com/thread.jspa?threadID=689209&tstart=0

A Google cache link is provided as the original forum thread can no longer be ac
cessed:
http://66.249.93.104/search?q=cache:KclmpSxZzEEJ:forums.java.sun.com/thread.jspa
%3FthreadID%3D689209%26tstart%3D0+%22java.util.MissingResourceException:+Can%27t
+find+resource+for+bundle%22+%221.5.0_06%22&hl=en&lr=&client=firefox-a&strip=1

We need to ensure that this issue is addressed, and that it will also be resolve
d in future version of the JRE.