java.lang.IllegalArgumentException: file:/home/feor58/lib/gwt-servlet.jar/ is not a valid classpath entry; use a jar-protocol URL.
   at org.netbeans.modules.java.classpath.SimplePathResourceImplementation.verify(SimplePathResourceImplementation.java:87)
   at org.netbeans.modules.java.classpath.SimplePathResourceImplementation.verify(SimplePathResourceImplementation.java:62)
   at org.netbeans.modules.java.classpath.SimplePathResourceImplementation.<init>(SimplePathResourceImplementation.java:105)
   at org.netbeans.spi.java.classpath.support.ClassPathSupport.createResource(ClassPathSupport.java:75)
Caused: java.lang.IllegalArgumentException: File: /home/feor58/lib/gwt-servlet.jar, Property value: /home/feor58/lib/gwt-servlet.jar, Exists: true, FileObject: valid
   at org.netbeans.spi.java.project.classpath.support.ProjectClassPathImplementation.getPath(ProjectClassPathImplementation.java:160)
   at org.netbeans.spi.java.project.classpath.support.ProjectClassPathImplementation.run(ProjectClassPathImplementation.java:122)
   at org.openide.util.Mutex.leaveImpl(Mutex.java:902)
   at org.openide.util.Mutex.leave(Mutex.java:835)
   at org.openide.util.Mutex.writeAccess(Mutex.java:439)
   at org.netbeans.modules.java.api.common.classpath.ClassPathModifierSupport.handleLibraryClassPathItems(ClassPathModifierSupport.java:257)
   at org.netbeans.modules.java.api.common.classpath.ClassPathModifierSupport.handleLibraries(ClassPathModifierSupport.java:225)
   at org.netbeans.modules.java.api.common.classpath.ClassPathModifier.handleLibraries(ClassPathModifier.java:184)
   at org.netbeans.modules.java.api.common.classpath.ClassPathModifier.addLibraries(ClassPathModifier.java:180)
   at org.netbeans.spi.java.project.classpath.ProjectClassPathModifierImplementation$Accessor.addLibraries(ProjectClassPathModifierImplementation.java:422)
   at org.netbeans.api.java.project.classpath.ProjectClassPathModifier.addLibraries(ProjectClassPathModifier.java:92)
   at org.netbeans.modules.java.api.common.project.ui.LibrariesNode$AddLibraryAction.addLibraries(LibrariesNode.java:677)
   at org.netbeans.modules.java.api.common.project.ui.LibrariesNode$AddLibraryAction.actionPerformed(LibrariesNode.java:661)
   at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
   at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
   at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
   at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
   at javax.swing.AbstractButton.doClick(AbstractButton.java:357)
   at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1223)
   at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1264)
   at java.awt.Component.processMouseEvent(Component.java:6263)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3267)
   at java.awt.Component.processEvent(Component.java:6028)
   at java.awt.Container.processEvent(Container.java:2041)
   at java.awt.Component.dispatchEventImpl(Component.java:4630)
   at java.awt.Container.dispatchEventImpl(Container.java:2099)
   at java.awt.Component.dispatchEvent(Component.java:4460)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4574)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4238)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4168)
   at java.awt.Container.dispatchEventImpl(Container.java:2085)
   at java.awt.Window.dispatchEventImpl(Window.java:2478)
   at java.awt.Component.dispatchEvent(Component.java:4460)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:133)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)