The text of the GPL was added to the source. Long options for the command line were added, and short options are no longer supported. The --enc=algo and --mac=algo options were added to choose the block cipher and the mac function used once the tunnel is established.
Support for forward secrecy was added. Even if an attacker cracks the box, he
won't be able to read traffic older than a specified delay (default 10
minutes). Other minor modifications were also made.