Null Pointer Exception when authentication fails

[dom3551]

When I call the Authenticate method on the pop client, I get the following exception:

System Error : System.NullReferenceException: Object reference not set to an instance of an object.
at OpenPop.Pop3.Pop3Client.CheckFailedLoginServerResponse(String serverErrorResponse, PopServerException e)
at OpenPop.Pop3.Pop3Client.Authenticate(String username, String password, AuthenticationMethod authenticationMethod)

This is also stopping me from seeing the login server response - is this a bug and is there any workaround so I can see the login server response?

Thanks