flickering in D90

Nikon D90 Problem Video waves flackert flickering from Young-Soo Chang on Vimeo.

just go to Nikon showroom today and found this problem for D90 in PAL world.

Solution suggested by el presidente in DVXUser forum:

"There is a workaround for this...you need a manual lens tho and its not perfect...you use exposure lock ...and point camera at a midtone with aperture shut a little..if you hold it on the wall or whatever and move camera around this minutely changes exposure and you will see momentarily the waves disapear..at that point use exposure lock then adjust using f-stop.no more nasty waves.not a perfect solution but it does work."

or use the light with Flicker-Free Ballast.