def set_sybase_service(database = nil, domain = nil, username = nil, password = nil)
      self.database         = database
      self.domain           = domain
      self.use_windows_auth = domain.nil?
      self.user_name        = username
      self.password         = password
      self.service          = Credential::Service::SYBASE
    end
def set_sybase_service(database = nil, domain = nil, username = nil, password = nil)
      self.database         = database
      self.domain           = domain
      self.use_windows_auth = domain.nil?
      self.user_name        = username
      self.password         = password
      self.service          = Credential::Service::SYBASE
    end
sets the Sybase SQL Server service.