Question on Duemilanove RX and TX pins

I need to interface my Duemilanove with a serial device, and would like to make use of the hardware UART on pins 0 and 1. Those pins are attached to the FTDI usb->serial chip on the board. Is it safe to still use pins 0 and 1 to communicate with another device? I'm just worried because on the RX line, the output of the FTDI chip will be connected to the output of the serial device I'll be controlling. I'm not worried about data collision because the USB interface will not be used.

Thanks! Sorry if this is answered elsewhere, I couldn't find any info.

If you don't have USB connected it's no problem at all.

You could also use SoftwareSerial on two of the other digital pins if you want to keep the USB connection available.

OK, cool. Thanks for your help.

Only thing to be careful of is make sure to always connect TX from one device to RX of the other device and vice-versa ;D