I have a requirement to issue a customized message only to e-mail
addresses belonging to a specific domain.

I attempted to modify the template SIGNUP1 as follows:

   .BB (&WHOM =* *@DOMAIN.NET)
   Custom message here.
   .EB
   Generic message here.

This produces an error at the beginning of the second condition argument.

Is this not the correct syntax?  Is this not allowed in this template?