I told about that problem (on the MTU setting) because it's very common on the internet and gave me some headaches for a few days (while I was searching for a solution). I've searched google with no luck, until I had the idea of contacting the live support on Linksys. They solved the problem in 5 minutes, if that much. Heheh, I guess I need to trust the tech support of the companies a bit more...
Anyway, the LAN side was always fine. The internet link was going down... what was requiring a reboot to work. When the DSL modem was at router mode and the Linksys internet link as DHCP, it was fine. However, I like to use things as simple as possible, and a much better solution is the modem as bridge and the internet on the Linksys configured as PPPoE, so I can avoid a nasty double-natting scheme.
