Date on your BB2

BB2 uses date from the server time stamp. On a traditional BB2 server the date is normally set by typing

#date -s "hh:mm:ss dd:mm:yyyy"

Also bear in mind Time Zones so to correct this on ubuntu type

#dpkg-reconfigure tzdata

This will allow you to correct the time zone of your bb2 server

Also have a look at your bb2_config.php file in the engine/conf/ direcorty you can control your date by time zone using php time zones.