Hello Jukka,

   JS> Using a different null modem cable, I can login on
     > both the console and tty01...Both cables seem to be
     > regular null modem cables; why does login on tty01
     > only works with one of them, but login on the console
     > works with both of them? Any hints?

I've seen quite a bit of variation between different "null
modem" cables.  Have you checked how yours are wired?  What
happens if you connect the one that doesn't seem to work
with tty01 the other way around, does it make a difference?

I make mine like this...

             DB  DB                        DB  DB
              9  25                        25   9
             ~~  ~~                        ~~  ~~
              3   2  TXD -----\/----- TXD   2   3
              2   3  RXD <----/\----> RXD   3   2

              7   4  RTS -----\/----- RTS   4   7
              8   5  CTS <----/\----> CTS   5   8

              4  20  DTR -----\/----- DTR  20   4
              6   6  DSR <-+--/\--+-> DSR   6   6
              1   8  DCD <-'      `-> DCD   8   1

              5   7  SG  ------------  SG   7   5

     ...if one or both ends are 25 pin, I connect the cable's
shield to pin 1 at one end only.  On 9-pin connectors the
shell is supposedly frame ground, so it's worth connecting
that at one end if neither end is 25 pin.

I hope that this helps.

- Andy Ball.