Hello Michel
Hmm, that’s strange. I tried to recreate your results, but I was unable to. In CML, I was able to get it to work as expected.
When you issue the show ipv6 interface brief command on R1, what do you see? Do you see Gi0/0 with a link local address assigned? Also, check to see if the interface has been enabled with the “no shutdown” command. In CML, when you create a new topology, and you configure a router port, they are always shutdown until you enable them. If you don’t enable the interface, you do get the “IPv6 isn't enabled on this interface” error message. Check it out and let us know!
I hope this has been helpful!
Laz