diff -r 00b69d7ccb4d autoupdate.services/test/unit/src/org/netbeans/modules/autoupdate/services/InstallHiddenModuleTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/autoupdate.services/test/unit/src/org/netbeans/modules/autoupdate/services/InstallHiddenModuleTest.java	Tue Feb 03 12:23:44 2009 +0100
@@ -0,0 +1,81 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
+ *
+ * The contents of this file are subject to the terms of either the GNU
+ * General Public License Version 2 only ("GPL") or the Common
+ * Development and Distribution License("CDDL") (collectively, the
+ * "License"). You may not use this file except in compliance with the
+ * License. You can obtain a copy of the License at
+ * http://www.netbeans.org/cddl-gplv2.html
+ * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
+ * specific language governing permissions and limitations under the
+ * License.  When distributing the software, include this License Header
+ * Notice in each file and include the License file at
+ * nbbuild/licenses/CDDL-GPL-2-CP.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the GPL Version 2 section of the License file that
+ * accompanied this code. If applicable, add the following below the
+ * License Header, with the fields enclosed by brackets [] replaced by
+ * your own identifying information:
+ * "Portions Copyrighted [year] [name of copyright owner]"
+ *
+ * Contributor(s):
+ *
+ * The Original Software is NetBeans. The Initial Developer of the Original
+ * Software is Sun Microsystems, Inc. Portions Copyright 1997-2007 Sun
+ * Microsystems, Inc. All Rights Reserved.
+ *
+ * If you wish your version of this file to be governed by only the CDDL
+ * or only the GPL Version 2, indicate your decision by adding
+ * "[Contributor] elects to include this software in this distribution
+ * under the [CDDL or GPL Version 2] license." If you do not indicate a
+ * single choice of license, a recipient has the option to distribute
+ * your version of this file under either the CDDL, the GPL Version 2 or
+ * to extend the choice of license to its licensees as provided above.
+ * However, if you add GPL Version 2 code and therefore, elected the GPL
+ * Version 2 license, then the option applies only if the new code is
+ * made subject to such option by the copyright holder.
+ */
+
+package org.netbeans.modules.autoupdate.services;
+
+import java.io.File;
+import org.netbeans.api.autoupdate.UpdateUnit;
+
+/**
+ *
+ * @author Jaroslav Tulach
+ */
+public class InstallHiddenModuleTest extends OperationsTestImpl {
+
+    public InstallHiddenModuleTest(String testName) {
+        super(testName);
+    }
+
+    @Override
+    protected void setUp() throws Exception {
+        clearWorkDir();
+        super.setUp();        
+        System.setProperty("netbeans.dirs", getWorkDirPath());
+        String udp = System.getProperty("netbeans.user");
+        assertNotNull("User dir is provided", udp);
+        File ud = new File(udp);
+        File hidden = new File(new File(new File(ud, "config"), "Modules"),
+            moduleCodeNameBaseForTest().replace('.', '-') + ".xml_hidden"
+        );
+        hidden.getParentFile().mkdirs();
+        hidden.createNewFile();
+    }
+
+    protected String moduleCodeNameBaseForTest() {
+        return "com.sun.testmodule.cluster"; //NOI18N
+    }
+
+    public void testSelf() throws Exception {
+        UpdateUnit install = UpdateManagerImpl.getInstance().getUpdateUnit(moduleCodeNameBaseForTest());
+        assertNotNull("There is an NBM to install", install);
+        installModule(install, null);
+    }
+}