Why do camllight and ocaml treat constructors differently?

In camllight I can write
    #type ip = Pair of int * int;;
   Type ip defined.
and the system recognizes Pair automatically as a value
    #Pair;;
    - : int * int -> ip = <fun>

Doing the same in ocaml (1.03) I get:
        # type ip = Pair of int * int;;
        type ip = Pair of int * int
        # Pair;;
        The constructor Pair expects 2 argument(s),
        but is here applied to 0 argument(s)

I do prefer the behavior of camllight especially for porting SML code.

Simon

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Simon Clematide
Stuessistr. 96
CH-8057 Zuerich
E-mail: sclematide@access.ch
Phone: +41 1 361 22 37