Sorry for the confusion. As of Arduino 1.0.2, Serial.begin() takes an extra (optional) parameter that defines the configuration of the serial connection.
Since it's so new, the only information I could find on it was some discussion on Google Code, and the Serial/Begin page.
I also tried snooping around the HardwareSerial code, but it's mostly over my head.
I'm not expecting parity errors, but if they happen I'd like to be able to handle them gracefully.