java.lang.ClassNotFoundException: org.eclipse.core.runtime.Plugin cannot be found by org.eclipse.mylyn.bugzilla.core_3.10.0.20131024-1218
   at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:501)
   at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
   at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
   at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
   at org.netbeans.modules.netbinox.NetbinoxLoader.loadClass(NetbinoxLoader.java:81)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
Caused: java.lang.NoClassDefFoundError: org/eclipse/core/runtime/Plugin
   at java.lang.ClassLoader.defineClass1(ClassLoader.java:0)
   at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
   at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.defineClass(DefaultClassLoader.java:188)
   at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClassHoldingLock(ClasspathManager.java:638)
   at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.defineClass(ClasspathManager.java:613)
   at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findClassImpl(ClasspathManager.java:574)
   at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClassImpl(ClasspathManager.java:492)
   at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:465)
   at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:216)
   at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:395)
   at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:464)
   at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:421)
   at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:412)
   at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
   at org.netbeans.modules.netbinox.NetbinoxLoader.loadClass(NetbinoxLoader.java:81)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
   at org.eclipse.osgi.internal.loader.BundleLoader.loadClass(BundleLoader.java:340)
   at org.eclipse.osgi.framework.internal.core.BundleHost.loadClass(BundleHost.java:229)
Caused: org.osgi.framework.BundleException: The activator org.eclipse.mylyn.internal.bugzilla.core.BugzillaCorePlugin for bundle org.eclipse.mylyn.bugzilla.core is invalid
   at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadBundleActivator(AbstractBundle.java:172)
   at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:679)
   at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:381)
   at org.eclipse.osgi.framework.internal.core.AbstractBundle.resume(AbstractBundle.java:390)
   at org.eclipse.osgi.framework.internal.core.Framework.resumeBundle(Framework.java:1176)
   at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:559)
   at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:544)
   at org.eclipse.osgi.framework.internal.core.StartLevelManager.incFWSL(StartLevelManager.java:457)
   at org.eclipse.osgi.framework.internal.core.StartLevelManager.doSetStartLevel(StartLevelManager.java:243)
   at org.eclipse.osgi.framework.internal.core.EquinoxLauncher.internalStart(EquinoxLauncher.java:271)
   at org.eclipse.osgi.framework.internal.core.EquinoxLauncher.start(EquinoxLauncher.java:241)
   at org.eclipse.osgi.launch.Equinox.start(Equinox.java:258)
   at org.netbeans.core.netigso.Netigso.start(Netigso.java:191)
   at org.netbeans.NetigsoHandle.startFramework(NetigsoHandle.java:209)
   at org.netbeans.ModuleManager.enable(ModuleManager.java:1195)
   at org.netbeans.ModuleManager.enable(ModuleManager.java:1017)
   at org.netbeans.core.startup.ModuleList.installNew(ModuleList.java:340)
   at org.netbeans.core.startup.ModuleList.trigger(ModuleList.java:276)
   at org.netbeans.core.startup.ModuleSystem.restore(ModuleSystem.java:301)
   at org.netbeans.core.startup.Main.getModuleSystem(Main.java:181)
   at org.netbeans.core.startup.Main.getModuleSystem(Main.java:150)
   at org.netbeans.core.startup.Main.start(Main.java:307)
   at org.netbeans.core.startup.TopThreadGroup.run(TopThreadGroup.java:123)
   at java.lang.Thread.run(Thread.java:745)