Then we finally fixed it:
Create a file in /etc/resolver named for your domain - for example
touch /etc/resolver/yourdomain.com
Then add the following to the file
nameserver w.x.y.z [I said:
<- your internal DNS IP obviously[/I]
domain yourdomain.com
port 53
That is what I have seen before however this is a permanent redirect for the domains you add. For example we have a public domain and with this work around you can then only get to it when your connect your vpn.
I was lucky add we use sub domains for internal links so I just used these instead.
e.g
test.domain.com and not just domain.com
Now when I am not on the vpn I can still get to the public domains.