Technically you are correct and that's what was taught to me in first year in college. In last year of highschool we were taught that photons don't have rest mass but they only have it when they move. Kind of similar but not quite but also a bit less confusing to understand.
Googling for "rest mass" to see if I translated it correctly I landed on this:
http://en.wikipedia.org/wiki/Photon#Experimental_checks_on_photon_mass
