dig returned following output. I used my vpn gateway address 192.168.210.1 for this.
pptp-client1@virtual-machine:~$ dig google.com 192.168.210.1
; <<>> DiG 9.8.1-P1 <<>> google.com 192.168.210.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: REFUSED, id: 27086
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;google.com. IN A
;; Query time: 1 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Wed Mar 20 11:38:42 2013
;; MSG SIZE rcvd: 28
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 54292
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;192.168.210.1. IN A
;; ANSWER SECTION:
192.168.210.1. 0 IN A 192.168.210.1
;; Query time: 0 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Wed Mar 20 11:38:42 2013
;; MSG SIZE rcvd: 47
Of course the internal name resolution works perfect.
pptp-client1@virtual-machine:~$ dig zentyal.lan 192.168.210.1
; <<>> DiG 9.8.1-P1 <<>> zentyal.lan 192.168.210.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 47108
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1
;; QUESTION SECTION:
;zentyal.lan. IN A
;; ANSWER SECTION:
zentyal.lan. 259200 IN A 192.168.122.209
;; AUTHORITY SECTION:
zentyal.lan. 259200 IN NS zentyal.zentyal.lan.
;; ADDITIONAL SECTION:
zentyal.zentyal.lan. 259200 IN A 192.168.122.209
;; Query time: 1 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Wed Mar 20 11:41:31 2013
;; MSG SIZE rcvd: 83
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 19011
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
;; QUESTION SECTION:
;192.168.210.1. IN A
;; ANSWER SECTION:
192.168.210.1. 0 IN A 192.168.210.1
;; Query time: 0 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Wed Mar 20 11:41:31 2013
;; MSG SIZE rcvd: 47