Can't login through ssh from 6.3 machine to 7.0 machine

[Frank Bonnet]

Hello

I have installed a fresh new machine running 7.0 and surprisingly
I cannot log in from another machine through SSH ...

I haven't modified the standard sshd configuration at install
which is the same than my other 6.3 based machine ...

All accounts are local.

I can    ssh 7.0 --> 6.3
I cannot ssh 6.3 --> 7.0

???

Thanks for any info.