i'm a Vicidial newbie, but i'm learning fast

last evening installed Vicibox at the office and played a little bit, using 6666/1234 login/pass.
Vicidial's ip is 10.10.100.107 (eth0)
Now i'm trying to access it via a vpn server and it does not accept login/pass..
Vpn's ip is 10.129.11.13 (ppp0)
I suppose there is a restriction on this ?
How can i access it? I do not want to expose it to internet..
regards,
George