Reply #40...http://arduino.cc/forum/index.php/topic,85207.msg641119.html#msg641119...next to "Reply #" there is a message icon. It is a link to that message. On this message it is an exclamation mark. The title over each message is also a link to that message.
A number of libraries access Serial. This causes HardwareSerial to be loaded even if you don't call the functions that access Serial. These libraries can't be used with SerialPort.All released SD.h and SdFat libraries cause HardwareSerial to be loaded and can't be used with SerialPort. I will soon release a version of SdFat that does not access HardwareSerial. A beta version of this SdFat is in SerialLoggerBeta20120108.zip here http://code.google.com/p/beta-lib/downloads/list.