This is a little modification of the common.php, I've added 2 lines, which will change the session save path to "temp" in the phpATM main directory.
This is for people who doesn't have write permission to the normal tmp folder and/or where PHP isn't setup properly.
You'll have to change the permission of the "temp" folder to make sure that phpATM can create files in that folder.
Also for security reasons I recommend to change the folder name (this requires to make changes to the common.php as well, search there for "temp"
and replace it with the new name.