this is how i got it working
Under Options>Preferences>Proxy/Firewall/Ident
1)Check "Limit Local Range"
2)I Select a hundred ports (just to be safe) I used 30000-30099
3) Check "Bind local ports to this IP:"
4) Enter your external IP address
5) In my firewall i created new rule to forward these ports to internal ip
I hope this will help others.
Thanks to all how responded
