This recent post might help.
http://www.irv2.com/forums/f258/no-water-187866.html
Anything can happen. Some MH are better insulated than others, some are built for summer vacation travel and do not have cold weather travel in mind.
Some MH's have a complete heated basements with a separate thermostat and are built for winter travel complete with heated floors where the pipes lay. Looking at the insulation and basement heating of your MH should help with your decision.