The pair attended the 2006 Los Angeles ceremony but found themselves locked out of the Kodak Theatre with Mickey Rooney.
"We went to the loo just before our award was announced," Park explained. "We actually got locked out and they wouldn't let us back in. I was panicking with the door person, trying [to get him] to let us in - Peter was having a good chat with Mickey Rooney, who was also locked out."
Sallis said that Rooney enquired about doing voice work in a future Wallace And Gromit instalment, while Park confirmed that another actor had asked to lend his vocal talents to Aardman Animation.
Park said: "Mark Hamill from Star Wars, we met him actually. His agent said he's very keen on doing voices."
Speaking about his experience at the Academy Awards, Sallis said: "I was thrilled, I've always been an Oscar fan. I love the girls, the actresses, who are in tears and thank their mummy and their daddy and the chap who looked after their dog. Just to be there was really lovely."
New Wallace And Gromit adventure A Matter Of Loaf And Death airs this Christmas on BBC One.