Continuity mistake: At the end, when John and Nadia are kissing goodbye at the airport, he puts the coat with the money over her shoulders. Her hair is outside the coat. In shots from behind, all of her hair is underneath the coat.
In the beginning of the film when John and Nadia are eating supper together, Nadia gives John a ring and speaks in Russian. The camera is at her back so we can't see her mouth move, but it is definately not Nicole Kidman's voice.