In case you still need an answer, I manged in the end
After various useless efforts, including installing IiLife09 "Support-Something" 9.0.3, repairing disk permissions and such sundries, what really worked was Syncing my iPhone via iTunes (including Photos) which did not copy new photos to my Mac, but then, in iPhoto, my iPhone was visible and accessible again.
Hope this helps. Cheers
F