Both TX and RX LED's are on at the same time?

Both TX and RX LED's are on at the same time? when connected to a USB and I can't upload to the Arduino. What's up with this? Anybody?

Can you tell us what board you are using? Is it an Arduino Duemilanove board?

Also do you have anything attached to pins 0 and 1?

It's a Arduino Duemilanove board, with nothing connected to it.

False alarm, it was pluged into a USB hub with a loose USB cable. it's working now. Thanks to all.