c# - Ninject's AllowNullInjection not working in ASP.NET WCF -

i using following ninject's nuget packages in asp.net wcf project:

• ninject
• ninject.web.common
• ninject.web.common.webhost
• ninject.extensions.wcf

my wcf service fooservice depends on irepository has concrete implementation foorepository this:

[servicecontract] public interface ifooservice {     [operationcontract]     ienumerable<foo> getfoos(); }  public class fooservice : ifooservice {     private readonly irepository _repository;      public fooservice(irepository repository)     {         _repository = repository;     } }  public class foorepository : irepository {     private readonly foocontext _foocontext;     private readonly ilogger _logger;      public foorepository(foocontext foocontext, ilogger logger)     {         _foocontext = foocontext;         _logger = logger;     } } 

fooservice.svc:

<%@ servicehost language="c#"                  debug="true"                  service="foonamespace.fooservice"                  codebehind="fooservice.svc.cs"                  factory="ninject.extensions.wcf.ninjectservicehostfactory" %> 

and set dependencies in ninjectwebcommon.cs this:

private static void registerservices(ikernel kernel) {     kernel.settings.allownullinjection = true;     kernel.bind<irepository>().to<foorepository>().inrequestscope();      // want bind null ilogger through settings property     // instead of manually calling bind<ilogger>().toconstant<ilogger>(null) }        

but still got activationexception when wcf service activated:

error activating ilogger no matching bindings available, , type not self-bindable. activation path:  2) injection of dependency ilogger parameter logger of constructor of type foorepository  1) injection of dependency irepository parameter repository of constructor of type fooservice 

how can set optional injection in case?