I think Curtis said something about learning the Cary Grant accent while serving on board a submarine during WW2. They had only one film on board: A Cary Grant film.
Joe E. Brown and Lemmon dancing at the roadhouse....
Jerry with the marracas.
"Gunga Din."
BTW, Tony Curtis did not do the voice of Josephine. That was dubbed in by Paul Frees (who also had a bit part as the "funeral director"). Paul Frees was THE voice man of the era (along with Mel Blanc), voicing dozens of familar cartoon characters and narrating and dubbing in lines in many movies.