Resource.getBundle does not give expected behaviour

A licensee has reported unexpected behaviour with getBundle method.

For this test case you need :-
test.java
testRes.properties
testRes_de.properties

The unexpected behaviour in the test case is the second usage of getBundle.
At the second usage of getBundle the default locale is de_DE and getBundle
is called with a current locale of en_US. The expected behaviour is that the
en_US resource file is used but instead the de_DE resource bundle is used.

# cat > testRes_de.properties
k3 = datum von heute: {0, date}

# cat > testRes.properties
k3 = date of today: {0, date}

# java test en
First usage of getBundle: default locale=en_US
Second usage of getBundle: default locale=de_DE desired locale=en_US
getString returned english (testRes)
date of today: {0, date} <=== Correct

# java test de
First usage of getBundle: default locale=de_DE
Second usage of getBundle: default locale=de_DE desired locale=en_US
getString returned german (testRes_de)
datum von heute: {0, date} <== I asked for en_US



import java.util.Locale;
import java.util.ResourceBundle;

public class test {

    public static void main (String[] args) {

        String initialDefault;
        ResourceBundle r;

        if (args.length == 0)
            initialDefault = "en";
        else
            initialDefault = args[0];

        if (initialDefault.equals("en"))
            Locale.setDefault(new Locale ("en", "US"));
        else
            Locale.setDefault(new Locale ("de", "DE"));

        System.out.println("First usage of getBundle:" +
                " default locale=" + Locale.getDefault());
        r = ResourceBundle.getBundle ("testRes", Locale.getDefault());

        Locale.setDefault( new Locale("de", "DE") );
        Locale desired = new Locale("en", "US");
        System.out.println("Second usage of getBundle:" +
                " default locale=" + Locale.getDefault() +
                " desired locale=" + desired.toString());

r = ResourceBundle.getBundle("testRes", desired );

        String s = r.getString ("k3");
        if (s.startsWith("date"))
            System.out.println("getString returned english (testRes)");
        else
            System.out.println("getString returned german (testRes_de)");

        System.out.println(s);
     }
}