1. Check the timestamp sudo reports (will look something like below).
    sudo: timestamp too far in the future: Jun 23 00:00:00 2007

2. Use Adjust Date & Time to set the date/time to the sudo timestamp or later.

3. Execute the 'sudo -k' command. (Clears the timestamp).

4. Use Adjust Date & Time to set the date/time back to the correct values.

Done.