Exceptions & IDE (part 2)

I apologize to everyone, damn Netscape cut off the rest of the message:
func b
  try
    raise Y
  except
    on Y do call a
  end
  THE LINE     <- here IDE breaks and places the current exec line marker
end b

So the function a raises the exception X while the exception Y is being
handled. I don't remember seeing anything in the chapter on exceptions if
this is allowed. In any case the program works just fine, exactly as I
expect it.
However the IDE breaks each time it happens, which can be frequent
occurance, so it is quite annoying. I can stop it by disabling debug
info, but then I can't debug the unit!
Does anyone have an explanation, clues hints?
Is nesting of exceptions Ok?

Slobodan Celenkovic

P.S.: Does Delphi have C/C++ bitstrings?