In the apartment Guilherme had rented for Camila, the doorbell sounds completely different in the two times it is rung (first when a boy is delivering flowers to her and then when it's Guilherme's lawyer who rings).
There is a version of McAfee VirusScan above 7.0 used in the movie which would be unavailable in 2001.
The Gradiente's GF-690 model cell phone, available from 2005 is featured in this movie set in 2001.
Modern money unavailable in 2001 is used (euro banknotes; 20 Brazilian real banknotes.)
In the scene where Camila is making out with Rodrigo, you can see the cameraman's shadow on Rodrigo's back in the shot where he throws her on the bed.