Deoxys's Speed Forme does not appear in this movie, as this movie was released before Pokémon Emerald; Speed Forme had yet to be introduced to the public.
For the American audience, this movie marks the first appearance of May's Bulbasaur. This is because King of the Forbidden Forest! Fushigibana!! (2004), in which May catches Bulbasaur, did not air in the United States until April 9, 2005, a little over two months after this movie was released.
May later obtained a Munchlax of her own.
In the dub, Brock tells Yuko that she reminds him of the time he worked for Professor Ivy. In the Japanese version, he says he's surprised that someone as young and beautiful as her could be a lab assistant and that he would also be a good assistant, never mentioning Professor Ivy.
This is the first Pokemon movie in which Jessie's Wobbuffet doesn't appear since Pokémon the Movie 2000 (1999), which was released before Wobbuffet was introduced in the anime.