Own my car for almost 5 years, the same problems kept happening on the driver's side door. I couldn't open from the outside but inside. It was covered under the warranty when I got it fix in 2009.
It happened again last January, and once again this January. I will pay around $350 to replace the door lock actuator. This problem did occur on the cold day like -10 centigrade.
I am looking forward to buy another brand new card this summer and it won't be from Nissan for sure.