Be able to set the times of the work day across midnight barrier

Here's another suggestion for functionality. It'd be nice to be able to specify when your work day starts and ends. I frequently stay up late working until after 2am, and then sleep and start working later the next morning. However, I'd like to count all the work I did (up till I went to sleep) as work done on the day before the work that starts again at 9 or 10am. Currently, slife reports all the work you've done between midnight to midnight, which makes it difficult to figure out individual "daily" work totals. This is especially important if you need to be able to report your "workday" productivity.