Date command does not follow Linux specifications (Mac OS X Lion)

man date indicates that it doesn't go beyond one second. I would recommend trying another language (Python 2):

$ python -c 'import time; print repr(time.time())'
1332334298.898616

For Python 3, use:

$ python -c 'import time; print(repr(time.time()))'

This is because OSX and Linux use two different sets of tools. Linux uses the GNU version of the date command (hence, GNU/Linux). Remember that Linux is Linux and OS X is Unix. They're different.

You can install the GNU date command which is included in the "coreutils" package from MacPorts. It will be installed on your system as gdate. You can either use that, or link the date binary with the new gdate binary; your choice.