FULL PRODUCT VERSION :
java version "1.5.0_14"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_14-b03)
Java HotSpot(TM) Client VM (build 1.5.0_14-b03, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
When using HttpsUrlConnection in in conjunction with authenticated proxies, an endless recursion can occur when the proxy reacts unexpected. See coding below.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the coding supplied, the ProxyConnect class first.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
ProxyTest should fail cleanly.
ACTUAL -
StackOverFlowError

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.io.InputStream;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * TODO_DOC add type comment
 * <p/>
 * @author Richard Birenheide (D035816)
 */
public class ProxyConnect {
	/**
	 * TODO_DOC add method comment
	 * <p/>
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args) throws Exception {
		ServerSocket ss = new ServerSocket(9000);
		while (true) {
			Socket s = ss.accept();
			InputStream is = s.getInputStream();
			byte[] buffer = new byte[10000];
			is.read(buffer);
			System.out.println(new String(buffer));
//			Thread.sleep(10000);
			s.getOutputStream().write("HTTP/1.1 407\nProxy-Authenticate:Basic realm=\"WallyWorld\"\n\n".getBytes());
			s.close();
			
			s = ss.accept();
			is = s.getInputStream();
			buffer = new byte[10000];
			is.read(buffer);
			System.out.println(new String(buffer));
//			Thread.sleep(10000);
//			s.getOutputStream().write("HTTP/1.0 407 \n\n".getBytes());
			s.close();
		}
	}
}

---------------------------------------------------------------------------------------------------
import java.net.Authenticator;
import java.net.InetSocketAddress;
import java.net.PasswordAuthentication;
import java.net.Proxy;
import java.net.URL;

import javax.net.ssl.HttpsURLConnection;

/**
 * TODO_DOC add type comment
 * <p/>
 * @author Richard Birenheide (D035816)
 */
public class ProxyTest {

	/**
	 * TODO_DOC add method comment
	 * <p/>
	 * @param args
	 */
	public static void main(String[] args) throws Exception {
		URL url = new URL("https://localhost:80");
		Authenticator.setDefault(new Authenticator() {
			@Override
			protected PasswordAuthentication getPasswordAuthentication() {
				System.out.println("Called");
				return new PasswordAuthentication("Test", "Test".toCharArray());
			}
		});
		HttpsURLConnection conn = (HttpsURLConnection) url.openConnection(new Proxy(Proxy.Type.HTTP, new InetSocketAddress("localhost", 9000)));
		conn.setAllowUserInteraction(true);
		conn.setUseCaches(false);
		conn.addRequestProperty("Proxy-Authorization", "blabla");
		conn.connect();
	}

}
---------- END SOURCE ----------