This should be automatic. I had a client have this problem once, and we found that the problem was actually with the 1310 being configured in diversity mode. The 1310 would disconnect in tough weather conditions and try to connect to the little metal stub that comes on the bridge. The signal was too weak to establish a good connection, but for some reason it would not switch back.
So check to see if you have diversity mode enable, and disable it if it is. If that's not the problem, I'm not sure what it could be. Have you tried upgrading the IOS?