Some tests that I've made a few months ago show that the design tools of ADP
(2000, 2002 and 2003) will not work against SQL-Server 2005 but the data
operations (querying, updating, call to stored procedures, etc.) work fine.
I've also heard somewhere that there is no plan actually to release a fixe
or a service pack to address this issue. (The real answer will come out in
a few days, when the next version of SQL-Server 2005 will be released. The
launch date is november the 7th.)
However, this is not a big deal because the design tools of SQL-Server
itself will be a suitable (and probably better) replacement.