According to http://www.cs.unc.edu/~dm/UNC/COMP205/LECTURES/ERROR/lec23/node4.html http://www.cs.unc.edu/~dm/UNC/COMP205/LECTURES/ERROR/lec23/n..., the system s

According to http://www.cs.unc.edu/~dm/UNC/COMP205/LECTURES/ERROR/lec23/node4.html http://www.cs.unc.edu/~dm/UNC/COMP205/LECTURES/ERROR/lec23/n..., the system stored the time in integers, but it was converted to floating point when doing the conversions. This conversion contained a small error that accumulated over time. Keep in mind that things that seem very WTF to you, might seem more plausible when given more details about the subject.