I just found this thread. I purchased a Motorola Atrix2 this weekend (Android 2.3.5). I installed the SS client and twice so far it has given me the "Network Error" message. It seems that this is happening when I'm sitting in my vehicle in my driveway (just on the edge of WiFi service). I then drive off and then my WiFi disconnects, but SS client still has issues connecting to the server. This just happened to me

My guess, is that this is related to a DNS issue. The reason I say this is that I set SS to use the DynDNS external name. I if I access that name from INSIDE my network, everything is fine. Outside as well. BUT, the IP changes between outside (98.xxx.yyy.zzz) and inside (10.0.0.z). So it seems that I need to force a DNS flush. This is my 2nd day with an Android phone, so I have no idea how to do that.

Or if the phone does do the DNS flush, it seems the SS app is somehow still using the old IP address. I'd love to test this further, but I'm not sure how. If there's a terminal app I can install on the Atrix, maybe that can give me an answer. I can try a ping by name and see what the IP comes back as. I suppose, if I have to, I can return this phone, and just get a Nexus S until the Galaxy Nexus comes out...
My Setup:
Ubuntu 10.10 x64
pfSense 2.0 release
DynDNS