initiate a logout to trigger the AuthenticationService.LoggedOut Event

Hi, im using the Application Services in a Client Application to authenticate the application remotely.
i used svcutil.exe AuthenticationService.svc?wsdl to create the conf file.
is there a way to initiate a logout in the same way ?
i would like to be able to use the AuthenticationService.LoggedOut Event on the server side.

if not, how is the AuthenticationService.LoggedOut Event trigered ? is there a timeout ? or is this only trigered when a user clicks the "logout" button ?

thanks

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