In the worksheet, a grade of zero is allowed, but not when scoring individual student

Version: 1:2.1.0-0ubuntu1 (afraid of updating since the database is holding everyone's grades needed for reports in a few days)
Ubuntu 12.04

There is a 100 point scale grade that was part of a deployed worksheet. When you are looking at the gradebook, you can type in the number 0 and save it. When you are scoring a specific student, it produces and error saying that 0 is an invalid score.