Mgmaps on a Moving Train

[Govind]

Hello,
I use Nokia E71 with Mgmaps installed using Yahoo maps. Recently while I was traveling in a moving train, I used GPS and amazingly it worked throughout my journey of about 500kms. I thought sat signals may be too weak to pick up inside of a train, but it is not so. Signals are best if the phone is held at the level of the window and near the window.
In My country traveling in a night train in a remote area(out of mobile network) could be a problem since you wont know where you are and how close you are to your destination so that you can prepare to get down from the train.
Govind Raj