This allows the tcp connection to send multiple SYN packets, so 1 lost
packet does not cause the mail to be lost. It changes the socket timeout
from 2 to 10 seconds, this allows for 3 syn packets to be send and
waiting a little for their reply.
This patch should be backported to 1.6.
Acked-by: Simon Horman <horms@verge.net.au>