ttyc/ttyd should be an allowed console device
Currently ttya and ttyb are the only ttys, which are allowed to be a console device.
This is a problem for none-SUN machines like SuperMicro MB X8DAH+-F (WPM450 BMC) driven ones, because here IPMI SOL is only possible, if the related BMC port is set to 0x3e8 (ttyc/COM3).
bdha found a workaround by attaching a "VT" aka ttymon to the related tty (e.g. ttyc) so that IPMI SOL works, but of course this has nothing to do with /dev/console ...
As far as I can see, a fix involves the following files (and some related includes), only: