I need to get an Uninterruptible Power Supply for my Xserve. A couple of times recently the power has gone out for a split second or so, and the Xserve failed to restart completely -- it came back online, and received email okay, but failed to send it out until I manually did a restart. A UPS should eliminate that problem, right? Any recommendation on what UPS to buy? I just want to cover outages that last a minute or less -- most are a second or less. Bob