Hi spuluka,
Your link shows that such a route IS required. In your the example given this would be the route below which is mateched when you need to send traffic over the VPN:
set routing-options static route 0.0.0.0/0 next-hop 1.1.1.1
Anyway as I said, on the local VPN gateway all these settings (policy, routing) seem OK. What I would like to see now is the configuration on the remote VPN gateway and the output of show security flow session as well when the ping is initiated on the local site. We need to make sure that the remove VPN receives the traffic, and if it does, that it also receives the return traffic.