This is correct: CA's are less a problem on film as compared to digital.
Basically: every lens that is not corrected apochromatic (and few are) has CA's. The longer the lens, the more critical the sensor and it shows up more severe. Lens manufacturers know this and correct their lenses as much as possible but true APO correction is horribly expensive (see the Leica 90/2.0 APO). Even my Zeiss PLanar 100/2.0 ZF has longitudinal CA wide open in some circumstances and this IS an expensive lens!
The Hexanon 90 is not specially APO corrected and made for film. It will indeed show CA on digital and you need to work this through in Photoshop to get rid of it. If this is really something you cannot live with then you can always save up for that APO CRON.....