Configuration Data for System User Dynamic Authentication

The Configuration Guide gives the following sample of configuration data for dynamic authentication modules:

<DialogUserDetect>

   <Usermappings>

      <Usermapping

         DialogUser = "dlg_kst"

         Selection = "select 1 where %uid% in (select uid_personhead from

         profitcenter)"/>

      <Usermapping

         DialogUser = "dlg_all"/>

   </Usermappings>

</DialogUserDetect>

Is there a comprehensive list of variables (like %uid% in the sample above) which may be used within this kind of XML config?

I would be mainly interested in performing a check against the Windows logon-id that is requesting authentication.

Thanks!