How do I connect to a terminal to a serial-to-USB device on Ubuntu 10.10 (Maverick Meerkat)?

First check with dmesg | grep tty if system recognize your adapter.
Then try to run minicom with sudo minicom -s, go to “Serial port setup” and change the first line to /dev/ttyUSB0.

Don’t forget to save config as default with “Save setup as dfl”. It works for me on Ubuntu 11.04 on VirtualBox.