I was asked to post a note here and in hopes of saving others frustration, here it is. There is a problem with the Uno serial firmware. To save me some time, the problem is described in detail here
http://arduino.cc/forum/index.php/topic,54618.0.html
and the fix for it is here
http://arduino.cc/en/Hacking/DFUProgramming8U2
The bug causes the sketch to hang and to reset each time it is addressed. The sketches will perform perfectly on a duemilanove but hang on a UNO.
The correct firmware is not in the Arduino download on the site. You have to follow the links and get Arduino-0022-45-gfcb66dd or later which was uploaded march 23 2011.
Hope this saves someone the hours it cost me to find and fix.
Uno Serial Bug
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Please be positive and constructive with your questions and comments.