Japanese mobile service provider Softbank announced today that it will sell satellite phones that can be used during tsunamis, earthquakes, or other events during which traditional mobile phone service may be unavailable. The carrier has partnered with Dubai-based Thuraya, a satellite phone and service provider, to sell satellite-based phones to its home market. Softbank, which is in the midst of a $20.1 billion acquisition of US carrier Sprint, has been slower than other Japanese carriers to restore critical mobile services