Internet address conflict between namespace and local.boot file

    I could certainly change this again in the namespace and simultaneously 
    edit the  local.boot file  typing  a command
    of the kind Set Network Address a-local-internet-number, but, somehow, 
    this looks strange.
    It is probably not the right way of doing things...

Why does it look strange to change the address in the Namespace and
in the Boot-File ? This should be the correct way of using the same
Lisp-World on several machines that are not Namespace-Servers. 

Since you have exactly one LispM at home it is probably a Namespace
Server. I would in that case boot the Distribution-World and use 
"Define Site" to define a completely new namespace containing the
2 hosts to be connected. Then the desired additional software (e.g.
Macsyma) can be loaded again and a new customized Lisp-World can
be saved. 


    Worse, several program requiring a password (like Macsyma)  no longer 
    work (of course, the password was
    given for MyIvory but the same machine now recognizes itself as 
    Internet|xxx.xxx.x;xx)

It it interesting to see that you are using Macsyma under Genera, 
because some years ago Richard Petti from Macsyma Inc told me that
I would be the only person who wants to use Macsyma under Genera.

However when you change the address of your Symbolics then you
will need a new Macsyma Key anyway. Furthermore you should be
sure that you got the machine including the Macsyma License.
Altough Macsyma Inc is now in "cold store" the owner of Macsyma 
Inc still insists in the license agreements. When you own the
Macsyma License you could contact Symbolics Inc for a new key
if you cannot determine it yourself.