~500 JCK tests fail if running in headless mode on windows 2003 with the message like:
------- 8< ----------------------------------------
java.lang.NoClassDefFoundError: Could not initialize class javax.swing.UIManager
    at javax.swing.JButton.updateUI(JButton.java:113)
    at javax.swing.AbstractButton.init(AbstractButton.java:2017)
    at javax.swing.JButton.<init>(JButton.java:103)
    at javax.swing.JButton.<init>(JButton.java:76)
    at javasoft.sqe.tests.api.javax.swing.BorderFactory.createXXXBorderTests.BorderFactory2003(createXXXBorderTests.java:97)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:585)
    at javasoft.sqe.javatest.lib.MultiTest.invokeTestCase(MultiTest.java:399)
    at javasoft.sqe.javatest.lib.MultiTest.run(MultiTest.java:195)
    at com.sun.jck.lib.ExecJCKTestSameJVMCmd$Version2Test.execute(ExecJCKTestSameJVMCmd.java:389)
    at com.sun.jck.lib.ExecJCKTestSameJVMCmd$StandardTest.run(ExecJCKTestSameJVMCmd.java:334)
    at com.sun.jck.lib.ExecJCKTestSameJVMCmd.execute(ExecJCKTestSameJVMCmd.java:211)
    at com.sun.jck.lib.ExecJCKTestSameJVMCmd.run(ExecJCKTestSameJVMCmd.java:140)
    at com.sun.javatest.agent.Agent$Task.executeCommand(Agent.java:818)
    at com.sun.javatest.agent.Agent$Task.execute(Agent.java:749)
    at com.sun.javatest.agent.Agent$Task.handleRequest(Agent.java:610)
    at com.sun.javatest.agent.Agent.handleRequestsUntilClosed(Agent.java:377)
    at com.sun.javatest.agent.Agent.access$000(Agent.java:41)
    at com.sun.javatest.agent.Agent$1.run(Agent.java:253)
    at java.lang.Thread.run(Thread.java:608)
------- 8< ----------------------------------------

Configuration we use:
jck: JCK 6.0 b06 qac
jdk: jdk 6.0 b47
test configuration: JCK-runtime singleJVM headless 32bit server Xmixed mode
platform: Windows 2003 Server/WindowsXP

Test execution result could be found at:
http://sqeel/java/jck/qa-results/jck/60/beta/b06/results/qac/r001api/windows-i586-050816135022/execdata/jtwork/report/filtered/newFailedTests.html

Some failing tests are listed below:
-----------------------------------
api/java_awt/BorderLayout/index.html#GetLayoutComponentByConstraints[getLayoutComponentByConstraints2001]
    api/java_awt/BorderLayout/index.html#GetLayoutComponentByConstraints[getLayoutComponentByConstraints2002]
    api/java_awt/Toolkit/index.html#Listener[Toolkit0010]
    api/java_beans/DefaultPersistenceDelegate/index.html#Methods[DefaultPersistenceDelegate2005]
    api/javax_accessibility/AccessibleRelation/index.html#Ctor[AccessibleRelation0002]
    api/javax_accessibility/AccessibleRelation/index.html#Ctor[AccessibleRelation0003]
    api/javax_accessibility/AccessibleRelation/index.html#target[AccessibleRelation0004]
    api/javax_accessibility/AccessibleRelation/index.html#target[AccessibleRelation0005]
    api/javax_management/foundation/Descriptor/index.html#GetFieldValuesTest02[doGetFieldValuesTest]
    api/javax_management/modelMBeans/ModelMBeans.html#ModelMBeanDescriptorTest0005[checkgetFieldValues]
    api/javax_swing/AbstractButton/AccessibleAbstractButton/index.html#AccessibleAction[AccessibleAbstractButton0012]
    api/javax_swing/ComponentInputMap/index.html#ctor[ComponentInputMap0002]
    api/javax_swing/ComponentInputMap/index.html#other[ComponentInputMap0003]
    api/javax_swing/JButton/index.html#updateUI[JButton2006]
    api/javax_swing/JCheckBoxMenuItem/AccessibleJCheckBoxMenuItem/index.html#AccessibleContext[AccessibleJCheckBoxMenuItem0001]
    api/javax_swing/JCheckBoxMenuItem/AccessibleJCheckBoxMenuItem/index.html#Ctor[AccessibleJCheckBoxMenuItem2001]
    api/javax_swing/JCheckBoxMenuItem/descriptions.html#Ctor[JCheckBoxMenuItem2001]
    api/javax_swing/colorchooser/ColorChooserComponentFactory/index.html#get[ColorChooserComponentFactory2002]
    api/javax_swing/event/ChangeEvent/descriptions.html#Ctor[ChangeEvent3001]