Console from HMC is not working

The console is the Java GUI console from HMC.

From ssh session, we ran these commands:
# lscons
/dev/null

# lsdev -Cc tty
vty0 available
vty1 defined
vty2 defined

# smitty console
-> assign the console to /dev/vty0

Rebooted after the console change. Things seem to be working ok again.