The D60 requires Camera Raw 4.4 (or later versions).
A new install of CS3 ships with Camera Raw 4.0 (which does not include D60 support).
So you need to install the latest version of Camera Raw which is compatible with CS3 (that's 4.6 which does include D60 support).
In Photoshop, click Help > Updates to update Camera Raw.
Or install manually
Adobe - Photoshop : For Macintosh : Camera Raw 4.6 update
Adobe - Photoshop : For Windows : Adobe DNG Converter and Camera Raw 4.6 update