PtoP IPv6 LL address with prefix 128 ?

In IPv4 is is common to use a /32 mask for PtoP IP addresses(aka unnumbered)
Trying to do the same for PtoP IPv6 LL address /128 does not work, OSPF stops
forming neighbours over such links, why?
Is there a fundamental difference between IPv4 and IPv6 in this case?

Also, I note I cannot telnet/ssh (Unable to connect to remote host: Invalid argument)
to a neighbour using its LL address without also specifying the interface(LL address%eth0).
Is there a knob around this?

 Jocke