Replicant

After generating the SSH keys with:

$ adb shell "/system/bin/ssh-keygen -A" 

Using the stock sshd_config with:

$ adb pull /etc/ssh/sshd_config
$ adb push sshd_config /data/ssh/sshd_config

$ adb shell "/system/bin/sshd" 
Could not load host key: /data/ssh/ssh_host_dsa_key

Commenting the following line in that configuration (and re-launching sshd):

HostKey /data/ssh/ssh_host_dsa_key