<p>I think I've come up with a partial answer. Whether the file is RAW or a jpeg, when I open it in Adobe Camera Raw or CS3 Photoshop, the profile remains AdobeRGB.<br>
However, when I import a RAW or jpeg file into <em>Aperture</em> and then export a version, I see an Embedded Profile Mismatch window, because the embedded profile is sRGB. And if I export a jpeg as an an original, I'm told it is missing a profile.<br>
So apparently the problem is in my Aperture settings. Not sure of my next step.</p>