I've just acquired an unlocked Acer Liquid MT running Android 2.3.6. It connects to WiFi in my home OK but after a variable period, minutes or hours, I see that WiFi is still "on" but not connected. If I toggle WiFi off-on I get "Error" and no WiFi. Rebooting the phone allows me to reestablish the WiFi connection. Is this a known issue? Is there a fix for it?