The kernel uses now /etc/urpmi/inst.list file to teach urpmi to
not remove old kernel binaries when doing an update. However
the kernel-header package can't be installed for now, see
https://qa.mandriva.com/show_bug.cgi?id=64160 and the reason is
that this package matches wrongly the regexp in inst.list. Therefore
urpmi tries to install the header package while keeping the old one
(linux-userspace-headers). This new version of urpmi simply excludes
kernel-headers packages from inst.list.