Debugging Challenge #1

Previously on Dr. Lambda's blog:

I have deviced a series of debugging challenges, some are easy, some are really hard, all come from real live systems. Good luck!

The Challenge

• 1 point if you can spot where the error is.
• +1 point if you can explain why.
• +2 points if you can explain how to fix it.

private static long IncrementRowVersion(long rowversion)
{
    return rowversion++;
}