I've spent days on this, looking at posts on Processing, Arduino, and other forums on the web.
I'm using Arduino 1.0.3, Processing 1.5.1 (I've gone back to a stable version), and Mac OS X 10.6.8.
I just want to run a simple sketch in processing to blink an LED on my Arduino Uno, and to read an analog value, just to make sure that serial communications between Arduino and the Mac are working correctly.

The first error I received was that the arduino libraries could not be found by Processing so I put the Arduino Library into the Processing>Libraries folder. And I moved back from the processing beta to 1.5.1.
Now I get the "infamous" RXTX Version Mismatch error when I try to compile in processing. There are extensive posts on this in the forums, I've seen references to java, jar, etc. but I don't know how to find and/or manipulate those files to solve this problem. I just can't find simple enough Mac instructions that I can follow (sorry if this is too simple).

Can someone please suggest a simple step by step solution? Thanks.