i cant get active-sync for the p990i i connected but i recive this error from the server

exception

javax.servlet.ServletException: failed to handle GET request
com.zimbra.cs.extension.ExtensionDispatcherServlet .service(ExtensionDispatcherServlet.java:111)
javax.servlet.http.HttpServlet.service(HttpServlet .java:802)
com.zimbra.webClient.filters.SetHeaderFilter.doFil ter(SetHeaderFilter.java:271)

root cause

com.zimbra.cs.service.ServiceException: system failure: Extension HTTP handler not found at /zimbrasync
com.zimbra.cs.service.ServiceException.FAILURE(Ser viceException.java:174)
com.zimbra.cs.extension.ExtensionDispatcherServlet .getHandler(ExtensionDispatcherServlet.java:146)
com.zimbra.cs.extension.ExtensionDispatcherServlet .service(ExtensionDispatcherServlet.java:99)
javax.servlet.http.HttpServlet.service(HttpServlet .java:802)
com.zimbra.webClient.filters.SetHeaderFilter.doFil ter(SetHeaderFilter.java:271)


i am using
zcs-4 open source

and the latest active sync from datavitz