datefudge binary package in Ubuntu Precise i386

 This program (and preload library) fakes the system date so that
 programs think the wall clock is ... different.
 .
 The faking is not complete; timestamp on files are not affected in any
 way.
 .
 This package is useful if you want to test the date handling of your
 programs without changing the system clock. Examples: Does it handle
 expired certificates correctly? Does it work on a leap day?

Source package