Solved Booting stopps after installkernel to RELEASE-11.0

Having done a reboot after make installkernel the monitor shows a blank screen with just that:
eval: vidcontrol: not found
And there it is stuck. I can ping the machine, but ssh is timing out.

The 10.3 system was configured for sc and zfs on root.

With a fixit I can mount the pool and edit files. I tried to rename the new kernel, but that does not help. The booting process stops somewhere, only a fat cursor can be seen in the upper left corner. The beastie menu does not appear.

I tried to edit loader.conf and rc.conf for sc and vt but that changes nothing when rebooting.
Any ideas?
Can you still boot to single user mode? You need to run mergemaster(8) in order to get the boot scripts sorted out. They're still the 10.3 ones.
Is the old kernel still around? Try boot /boot/kernel.old/kernel