As Andy suggests have a play with the saturation if you think the images look lifeless.
Regarding the digital rebel - I'm assuming you mean what's know as the 300D in Europe - as someone who has actually _used_ one there is no reason why the images should look flat unless there is a processing issue. See attached photograph. If you go to my website and look at the Australia 2005 album or Southern France 2004 you'll see more dull and lifeless shots :-)
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