Software Doesn't List Serial Ports

Hello!
I'm having a problem similar to the one found in http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1291458476, but I couldn't solve mine using the advice in that thread. I'm attempting to use a Duemilanove with Arduino 0022 installed manually in Ubuntu 10.10. However, no matter what I try, the Serial Port menu in the software is unselectable, and I can't connect to the Arduino. I believe that I already have all required packages installed, but I can't seem to find the Duemilanove through any method (ls, manually looking, etc.) Is it possible that there is an issue with my USB Serial drivers? If not, do you have any suggestions?
Thanks in advance!

Hi, another guy had this same problem, he had two (2) bad usb cables, the third one worked.

Let us know if switching the cable works.

if it does not, with the duemilanove usb port plug in and has power applied, open up a terminal and type:

lsusb

post the results. this will tell if the kernel modules are being loaded.