Date stamp does not compensate for time zone differences

example: Create a filter with 'Created After'=04/Oct/06 and 'Created Before'=06/Oct06.

I'd expect the system to return issues created on 05/Oct/06, but I get some that are created on 04/0ct/06 -all are within 8 hours of midnight. I assume the server time (Perth) is set for those issues logged in timezones that correlate to Perth time on 05/Oct/06. The system is not compensating for these differences.