CNAT comes with a component called a MibScanner.  You can run any mib that you
want through it and it will parse it looking for attributes that contain ip
addresses that need to be translated.  This creates a .oid file that you can
load into the CNAT machine.  When a specific attribute is sent through the cnat,
it looks in the .oid files and sees if it needs to be translated, so as long as
the customer has this private mib they are talking about, CNAT should be able to
translate it.  I hope this helps.