[CentOS] centos modprobe ipv6 fatal ipv6.ko Invalid module format

Hi. My provider rebooted the server today or the server rebooted itself
because of some problem, still don't know. Anyway: In /var/log/messages now
I get zillions of
modprobe: FATAL: Could not read
'/lib/modules/2.6.32-220.17.1.el6.x86_64/kernel/net/ipv6/ipv6.ko': Invalid
module format
I am not able to find any solution to this. ???
Thanks for your time,
Jesus