SuSE over written by Mandrake

I have SuSE V7 as my main Linux but installed Mandrake V7.1 on a different HD but it seems to have over-written something in my SuSE setup as it now says the PPP protocol is not in the Kernel preventing me from dialling out installing a different Kernel has no effect. If I boot from the SuSE DVD and then select boot from installed system its fine. I did upgrade to SuSE V7 prior to the Mandrake update – would it be better to revert to SuSE V6.4 and update again or is there an easier fix ??