try to read output in telnet carefully.
DSS and RSS keys are no more stored in nvram, but in /usr/local/etc/dropbear
In 1.7.5.9-5 there is flashfs command to save, commint, and enable for
flashfs save
flashfs commit
flashfs enable
an then run sshd from bootcmd or with post-boot commands
example sshd. BootCmds will by removed soon i think