SITE-TO-SITE - No matching phase2 found

Hello everyone, I have some trouble when creating a SITE-TO-SITE connection between FORTIGATE 200B and a Checkpoint EDGE device (its a small appliance like SBOX, it is not an NG firewall). PLEASE NOTE: The " outside" interface that I use is a VLAN interface which is assinged to the LAN interface on the FORTIGATE. However this VLAN interface has a PUBLIC ip address and is accessable from the remote peer. I have configured the connection on the FORTIGATE 200B as an route based VPN (by using an IPSEC interface in the phase1). On the FORTIGATE lan site I created a LOOPBACK interface with an address of 10.10.10.10/32. On the remote peer I have a class C subnet 192.168.10.0/24. The policies and the static route are created. After creating all that I simply initiated PING command from the remote peer' s lan to the LOOPBACK interface and tunnel came up (both phase 1 and 2). HOWEVER, there is no reply and afer about 10 to 15 seconds there is a message on the remote peer' s log that says: " Failed to establish VPN tunnel: invalid SPI x.x.x.x" On the FORTIGATE debug output it says : :error processing quick-mode message from [EDGE ip address] as responder :no matching phase2 found The phase 2 exists on both peers and it matches exactly. However the FORTIGATE debug says otherwise. Does anyone has any ideas ? Thanks