Error compiling widget

hi …
Im getting the following error while compiling any widget (touchkit , webcam),

[ERROR]
Errors in ‘jar:file:/home/sw205/Desktop/Vaadin%20with%20Mobile/gwt-user.jar/gwt-user.jar!/com/google/gwt/user/client/History.java’
[ERROR]
Line 62: Rebind result ‘com.google.gwt.user.client.impl.HistoryImplTimer’ could not be found
[ERROR]
Cannot proceed due to previous errors
/home/sw205/NetBeansProjects/AppletIntegration/build-widgetset.xml:67: Java returned: 1

can anyone having idea…
thanks