{error,timeout} with gethostbyname

[info]

Hi all,
On a windows 2003 server sbs this command returns {ok,"my_host"} :

{ok,N}=inet:gethostname().

But the following command returns {error,timeout} :

inet:gethostbyname(N).

On a Vista machine, the previous command returns a correct answer.

I know that it is not an erlang problem but if you could give me support, I will appreciate ;-)