Propane Tanks N Cold weather

I just came back from a Camping weekend and have one of those LP Fire pits. Using a Propane bottle for the fuel and it being cold outside, apx 34F the tank would freeze up. More than several times, the flame would "Flame out". If I shook the bottle, I could re-ignite it and it'd work for little longer, then do the same. Several times, then the tank would be empty.
I thought at first it was just cause it was running low, but the time it took to completely run out was a fairly long time, not like it was the last drop of propane.
I thought it could be due to the ice/freezing point on the bottle and found that if I put the tank in little rubber dish wash bucket and then poured hot water over it, it would "Flame UP" again and then die down.
So my question is.
Does it flame out due to the coldness, freezing on the side of the bottle which indicates it's cold. (actually sticks to the ground and also forms and ice ring around the bottom) or just that it might be low on Propane and needs to be "Shaken, not stirred..." like Bond, to I guess, expand the Propane??
Is there any solution??? for cold weather propane bottles???
thanks..
http://www.poolesweb.com/gallery/eagles ... s-1037.jpg
I thought at first it was just cause it was running low, but the time it took to completely run out was a fairly long time, not like it was the last drop of propane.
I thought it could be due to the ice/freezing point on the bottle and found that if I put the tank in little rubber dish wash bucket and then poured hot water over it, it would "Flame UP" again and then die down.
So my question is.
Does it flame out due to the coldness, freezing on the side of the bottle which indicates it's cold. (actually sticks to the ground and also forms and ice ring around the bottom) or just that it might be low on Propane and needs to be "Shaken, not stirred..." like Bond, to I guess, expand the Propane??
Is there any solution??? for cold weather propane bottles???
thanks..
http://www.poolesweb.com/gallery/eagles ... s-1037.jpg