Or. . research how to use your pc as a Proxy.
If that doesnt work, try setting up a DMZ between your PS3 and your DSL router. That worked for me in the GT5 days and for Battlefield 3 PS3 days when I got errors when downloading updates.
My ps3 died, it can't read the discs. I bought a new one, but it just won't let me transfer the data to the new console. I followed exactly the instructions with the cable and stuff, but it doesn't work.