Hello Tony,   
      
   On Wednesday January 31 2018 09:05, you wrote to me:   
      
    MvV>> Your mailers however are both client and server. They could   
    MvV>> still use the IPv4 address from the dual stack connection for   
    MvV>> outgoing connections. (if so confugured).   
      
    TL> Not by default, because the default gateway configuration has to be   
    TL> changed on the BBS machine.  The tunnel does not terminate on the main   
    TL> router.   
      
   Your router does IPv4 NAT, doesn't it? So every machine will get an RFC1918   
   IPv4 address won't it?   
      
   Have you configured your mailers to only use the VPN tunnel for IPv4?   
      
   Oh well, who cares, IPv4 is technology on the way out. In ten years it will be   
   a non-issue anyway. ;-)   
      
      
   Cheers, Michiel   
      
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