SSG140 Site to Site VPN with ASA Multiple Subnets

Hi;

Here is my cases.

Site A : SSG 140 firmware 6.2 (subnet: 192.168.70.x)

Site B : ASA (subnet 192.168.50.x)

Site C: HQ (subnet 10.10.x.x)

Site A <--- site to site VPN --> Site B   (SSG140 and ASA)

Site B <---- T1 link ---> Site C  (Router B1 to Router C1 via T1)

Currently, my computer at Site A communicate with Site B no problem.

What configuration is required to allow the traffic for Site C from Site A traverse the existing site to site VPN tunnel.

Please see my network diagram example file.