Open Source VPN Client for Mac?

Open Source VPN Client for Mac?

Hello i am looking for a good open source VPN client(MAC) which has made
its source code available so that i can modify it to redirect all HTTP
port 80 traffic to specific configured IP. I have tried
tunnelblick(tunnelblick github) but its source code wont run on xCode 4.6
citing Unsupported compiler 'GCC 4.2' selected for architecture 'i386'
issue. Can any one tell me how to successfully redirect particular port
traffic to a configured IP or any good open source VPN client which can be
modified?