*October 27, 2005 - *Canon released firmware updates Tuesday for the 20D and Rebel XT DSLRs. The 20D previously had a minor problem with the Speedlite 430EX communicating color temperature, and the Rebel XT had problems communicating with the wireless RC-1 controller and ceasing auto play during playback. The firmware updates for all three cameras also improve CF card communication.
Though the 20Da DSLR is very similar to the 20D, no firmware updates have yet been officially posted on the 20Da’s Support webpage.
Updates for the 20D can be found here: http://consumer.usa.canon.com/ir/controller?act=DownloadDetailAct&fcategoryid=325&modelid=10464#firmware
The Rebel XT’s update can be found here: http://consumer.usa.canon.com/ir/controller?act=DownloadDetailAct&fcategoryid=325&modelid=11154#firmware