Do you have any samples? I had to dig into my files to find some samples where there is visible ghosting or flare but none of the photo's I took with this lens have it in a disturbing way. In fact I never really noticed it before. Note that I'm (occasionally) using this lens on a 5DMkII (never on my 7D).
BTW the MkII is designed to be a cheaper, simpler re-issue of the MkI so I doubt Canon decided to up the standard with improved lens coatings. If anything I imagine the manufacturing quality control of the MkI should beat the MkII.
Flares and ghosting are not an issue with this lens (it's a small gauss with a small front lens, I guess that even a very old coating would do the work) I just remember that with the MKII was nearly impossible to get any ghosting, while with this one you can see a little decrease in contrast, in extreme situations.
I made an online research and find out that for the MKII Canon is using "the new super spectra coating". I don't know how "new" this coating is, but maybe it is too new for the MKI...
FWIW the Mk I was replaced by the Mk II in 1990 so both these lenses are designed for film. Therefore I wouldn't expect the coatings to be optimized for the reflections typical of an imaging sensor.