if you mean the .cur file type, i would go with the same mime type as the .ico (image/vnd.microsoft.icon) based on the following.

Microsoft Windows Cursor and Icon:
http://www.iconolog.org/info/icoFormat.html [iconolog.org]

Thanks, Safari and Chrome report it as having some mime error though I think that's the way my server is configured unless there is a known rejection of that media type by the WebKit team? I will survive regardless, the cursors work fine. Thanks!

- John