This is from bugzilla bug: http://bugzilla.mozilla.org/show_bug.cgi?id=80685

Reproducible: Always
Steps to Reproduce:
1. Go to http://www.dreamone.com/
2. Notice applet with peom quote works
3. Go to http://www.dreamone.com/testes/
4. Input username "testing" password "test" to browser
5. input username "testing" password "test" to Java applet
6. Notice applet does not work.

This is from my own analysis.

Problem 1: The Sun java plugin doesn't check for a null return from
Authenticator.getRequestingSite here:

D:\Projects\ladybird\ext\plugin\java\src\sun\plugin\PluginAuthenticator.java
getPasswordAuthentication():

// Request the username/password from the user
pa = openDialog(getRequestingSite().toString(), getRequestingPrompt(), getRequestingScheme());

This causes the password dialog not to be opened, which causes the
applet to fail.

Problem 2:

The reason getRequestingSite() returns null is in:

D:\Projects\ladybird\src\share\classes\sun\net\www\protocol\http\HttpURLConnection.java
getServerAuthentication()

if (ret == null) {
try {
addr = InetAddress.getByName(url.getHost());
} catch (java.net.UnknownHostException ignored) {
// User will have an unknown host.
System.out.println("debug: edburns: Unknown host, plugin gets NullPointerException");
}
}

When I recompile the HttpURLConnection.java and run with the recompiled
class, the error message is:

debug: edburns: Unknown host, plugin gets NullPointerException: url: http://www.dreamone.com/testes/dreams.class

For some reason, InetAddress.getByName() is failing.

I have posted a fix to the "Suggested Fix" section. This fix allows the applet to work on my machine.