Attempt to connect to sshd using the original ssh client (not openssh) version 1.2.33 fails. When option -v is used, the last two lines of output are Waiting for server public key. Local: Bad packet length 1349676916 The exact same situation worked with FC3's sshd.
The protocol 1 support is switched off in the /etc/ssh/sshd_config. You can modify this config file to enable the protocol 1 support if you really need it.