Billy Bob Thornton was offered the part of Abe but was unavailable. Bill Paxton turned the part down. Gary Cole auditioned and was offered the part but he could not fit it into his schedule. Christopher McDonald was cast in the role the night before filming started. While McDonald was on the set, he discovered that he could not fit it into his schedule. The role was then offered to Christopher Lloyd but he turned it down to do Haunted Lighthouse (2003). The role was finally given to William Sadler, who arrived on set and had only 60 minutes to meet and form a relationship with Shia LaBeouf before their big emotional scene together.
Christopher McDonald was originally cast in the role of Abe, but the role was recast (due to a scheduling conflict) and given to William Sadler the day before Abe's first scene was to be shot. McDonald was shown on Project Greenlight (2001) coming to the set for a wardrobe fitting mere hours before he was replaced.
During the battle sequence in the opening of the movie, the actors playing the German soldiers, including 'Shia Labeouf' disguised as one, all took lessons on how to speak German properly prior to filming of the scene.
Liv Tyler was offered the role of Tabby but passed. Jane Kaczmarek was offered the role of Eve at Miramax's insistence - over the objections of the directors - but passed and was replaced by the director's choice for the role: Kathleen Quinlan.
The test screenings showed that the audience had trouble figuring out whether it was a comedy or a teen drama. Directors Kyle Rankin and Efram Potelle and Miramax were fighting towards the end of post production on what genre it should be. The directors felt it should be a teen drama, Miramax thought it should be a comedy (because it was a marketing genre). Rankin and Potelle eventually gave in and cut it as a comedy.