[Guy Harris <guy@xxxxxxxxxx>]

> Well, I guess there is no real reason why it would not work in tethereal.
> However, and as I meant, these options can not (as far as I know) as well as 
> any other options be enabled from the tethereal command line.
> I might be wrong?

You are.  The "-o" option can be used to enable options from the command
line, in Ethereal or Tethereal - and the default values, for Tethereal
as well as Ethereal, are read from the preferences file.