We don't have any specific code that deals with SAN's. It's all transparently handled by .NET when we use filepaths that coincide with SAN capabilities. I'm sure it could maybe be something that we add. I feel like SM probably should have recovered automatically when the file availability comes back. Are your system files also stored on the SAN?, if so I'd advise against putting your system files on a SAN. Either way, we don't really have code that detects that it all the sudden can't access a file (that it previously was accessing) so we have no way to really recover and I'm not really sure what kind of behavior this could cause internally to SM.
Even if we did continue to run without being able to access those files many parts of the application would throw exceptions when we go to save files etc. Maybe you can set up your service monitor to automatically reboot your mailservice?