Currently, Arduino 0017 doesn’t work in 64 bit Linux, including Ubuntu 9.04. Arduino includes a copy of libRXTX, which is for 32 bit systems. Ubuntu only offers up to librxtx 2.1 something as of August 2009, and that doesn’t help either.
There’s a pretty quick way to get everything working–even the Serial Monitor!
The solution is to download Arduino 0017 for 32 bit Linux. Extract the files, and remove lib/librxtxSerial.so and RXTXcomm.jar.
Download rxtx-2.2pre2-bins from the RXTX folks. Extract the files, and copy RXTXcomm.jar and x86_64-unknown-linux-gnu/librxtxSerial.so to the Arduino lib/ directory, basically replacing the two files that came shipped with Arduino 0017.
Doing this doesn’t enable any other java application on your system to use the newer RXTX libraries, but that isn’t a problem for me. I’d much rather keep the rest of my system using packages from the repositories. The Arduino devs seem to be completely on top of the problem and the Ubuntu devs are aware as well.