How do I set system time and date from terminal ubuntu ?

you can do that by typing in the following format:

sudo date mmddHHMMYYyy

so
sudo date 060702031980
Sat Jun 7 02:03:00 IST 1980

or

Set hwclock manually:
# hwclock --set --date="9/22/96 16:45:05"

Yes for some reason debian and ubuntu are very date sensitive.