FULL PRODUCT VERSION :
C:\Windows\system32>java -version
java version "1.7.0-ea"
Java(TM) SE Runtime Environment (build 1.7.0-ea-b136)
Java HotSpot(TM) 64-Bit Server VM (build 21.0-b06, mixed mode)

C:\Windows\system32>


ADDITIONAL OS VERSION INFORMATION :
Windows 6.1.7600

EXTRA RELEVANT SYSTEM CONFIGURATION :
Windows 7 image is running under VMWare Fusion on a Mac OS PowerBook, not sure if that matters or not.

A DESCRIPTION OF THE PROBLEM :
Netbeans JUnit test suite runner fails if the Java platform is changed from 1.6.0_24 to 1.7.0-ea-b136 with the following stack trace when a test suite is run on Windows 7 x64:

Exception in thread "main" java.lang.AssertionError: Default directory must be absolute/non-UNC
        at sun.nio.fs.WindowsFileSystem.<init>(WindowsFileSystem.java:60)
        at sun.nio.fs.WindowsFileSystemProvider.<init>(WindowsFileSystemProvider.java:52)
        at sun.nio.fs.DefaultFileSystemProvider.create(DefaultFileSystemProvider.java:36)
        at java.nio.file.FileSystems$DefaultFileSystemHolder.getDefaultProvider(FileSystems.java:108)
        at java.nio.file.FileSystems$DefaultFileSystemHolder.access$000(FileSystems.java:89)
        at java.nio.file.FileSystems$DefaultFileSystemHolder$1.run(FileSystems.java:98)
        at java.nio.file.FileSystems$DefaultFileSystemHolder$1.run(FileSystems.java:96)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.nio.file.FileSystems$DefaultFileSystemHolder.defaultFileSystem(FileSystems.java:95)
        at java.nio.file.FileSystems$DefaultFileSystemHolder.<clinit>(FileSystems.java:90)
        at java.nio.file.FileSystems.getDefault(FileSystems.java:176)
        at sun.util.calendar.ZoneInfoFile$1.run(ZoneInfoFile.java:482)
        at sun.util.calendar.ZoneInfoFile$1.run(ZoneInfoFile.java:477)
        at java.security.AccessController.doPrivileged(Native Method)
        at sun.util.calendar.ZoneInfoFile.<clinit>(ZoneInfoFile.java:476)
        at sun.util.calendar.ZoneInfo.getTimeZone(ZoneInfo.java:658)
        at java.util.TimeZone.getTimeZone(TimeZone.java:559)
        at java.util.TimeZone.setDefaultZone(TimeZone.java:656)
        at java.util.TimeZone.getDefaultRef(TimeZone.java:623)
        at java.util.TimeZone.getDefault(TimeZone.java:610)
        at java.text.SimpleDateFormat.initializeCalendar(SimpleDateFormat.java:682)
        at java.text.SimpleDateFormat.<init>(SimpleDateFormat.java:581)
        at org.apache.tools.ant.util.DateUtils.<clinit>(DateUtils.java:69)
        at org.apache.tools.ant.util.DateUtils.<clinit>(DateUtils.java:69)
        at org.apache.tools.ant.taskdefs.optional.junit.XMLJUnitResultFormatter.startTestSuite(XMLJUnitResultFormatter.java:121)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.fireStartTestSuite(JUnitTestRunner.java:719)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.run(JUnitTestRunner.java:506)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.launch(JUnitTestRunner.java:1052)
        at org.apache.tools.ant.taskdefs.optional.junit.JUnitTestRunner.main(JUnitTestRunner.java:906)


REGRESSION. Last worked in version 6u24

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run a JUNIT test suite under Netbeans 6.9.1 with 1.7 ea on Windows 7 64.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Expected same result as JDK 1.6.0 23 or 24, i.e. successful run of test suite
ACTUAL -
The stack trace given above was produced.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
"BeforeFirstTest caused an ERROR: Forked Java VM exited abnormally"

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;
import static org.junit.Assert.*;

/**
 *
 * @author Norris Merritt
 */
public class NewEmptyJUnitTest {

    public NewEmptyJUnitTest() {
    }

    @BeforeClass
    public static void setUpClass() throws Exception {
    }

    @AfterClass
    public static void tearDownClass() throws Exception {
    }

    @Before
    public void setUp() {
    }

    @After
    public void tearDown() {
    }

    // TODO add test methods here.
    // The methods must be annotated with annotation @Test. For example:
    //
    @Test
     public void hello() {}

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

CUSTOMER SUBMITTED WORKAROUND :
None found