Shadow rendering exception

In Ardor3D I get the following exception in some of our machines when enabling shadow:

Apr 10, 2013 2:59:23 PM com.ardor3d.extension.shadow.map.ParallelSplitShadowMapPass init(Renderer)
SEVERE: Could not load shaders.
java.io.IOException: Stream closed
        at java.io.BufferedInputStream.getInIfOpen(BufferedInputStream.java:151)
        at java.io.BufferedInputStream.available(BufferedInputStream.java:399)
        at com.ardor3d.renderer.state.GLSLShaderObjectsState.load(GLSLShaderObjectsState.java:223)
        at com.ardor3d.renderer.state.GLSLShaderObjectsState.setVertexShader(GLSLShaderObjectsState.java:178)
        at com.ardor3d.renderer.state.GLSLShaderObjectsState.setVertexShader(GLSLShaderObjectsState.java:174)
        at com.ardor3d.extension.shadow.map.ParallelSplitShadowMapPass.init(ParallelSplitShadowMapPass.java:322)
        at com.ardor3d.extension.shadow.map.ParallelSplitShadowMapPass.updateShadowMaps(ParallelSplitShadowMapPass.java:455)
        at com.ardor3d.extension.shadow.map.ParallelSplitShadowMapPass.doRender(ParallelSplitShadowMapPass.java:446)
        at com.ardor3d.renderer.pass.Pass.renderPass(Pass.java:63)
        at org.concord.energy3d.scene.SceneManager.renderUnto(SceneManager.java:442)
        at com.ardor3d.framework.jogl.JoglCanvasRenderer.draw(JoglCanvasRenderer.java:247)
        at com.ardor3d.framework.jogl.JoglDrawerRunnable.run(JoglDrawerRunnable.java:16)
        at jogamp.opengl.GLRunnableTask.run(GLRunnableTask.java:59)
        at jogamp.opengl.GLDrawableHelper.execGLRunnables(GLDrawableHelper.java:619)
        at jogamp.opengl.GLDrawableHelper.display(GLDrawableHelper.java:559)
        at javax.media.opengl.awt.GLCanvas$6.run(GLCanvas.java:1027)
        at jogamp.opengl.GLDrawableHelper.invokeGLImpl(GLDrawableHelper.java:1021)
        at jogamp.opengl.GLDrawableHelper.invokeGL(GLDrawableHelper.java:896)
        at javax.media.opengl.awt.GLCanvas$7.run(GLCanvas.java:1038)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:241)
        at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:727)
        at java.awt.EventQueue.access$200(EventQueue.java:103)
        at java.awt.EventQueue$3.run(EventQueue.java:688)
        at java.awt.EventQueue$3.run(EventQueue.java:686)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:697)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

two additional lines of error that may be useful:

Apr 10, 2013 2:59:35 PM com.ardor3d.scene.state.jogl.JoglShaderObjectsStateUtil sendToGL
WARNING: Could not find shader resources!(both inputbuffers are null)

ResourceLocatorTool.getClassPathResourceAsStream() seems to return a closed stream in your case. I don't know why it happens but it has nothing to do with JOGL, it occurs in the binding-agnostic code.