The 1993 NEC explicitly allowed the white wire to feed a switch without being remarked. I didn't pickup the change, which was by 2002 and may have been 1999. If the light was wired under the 1993 (1996?) (or probably earlier) NEC it is code compliant (though remarking is a good idea).
===================== The current language (above) does not appear to allow power feed to a light, with 3 wire romex to 3-way switches (or 3 and 4-way switches). The feed to one 3-way with the white as supply would be compliant. Wiring to the other 3-way and 4-ways does not appear to comply. I would not call travelers a "supply" wire. I do not see how you can use a remarked white wire to a 4-way switch, mentioned above.
The way I read the language you have to wire power to 3?way (to 4?way) to 3-way to light.