No idea. I didn't originally created this comment. This method was initally created by copying GitIndex.Entry.ismodified() where this comment was introduced.

But it's seems to be that different filesystems have different precisions. Ext3 supports only a precision of seconds. See:  http://www.coderanch.com/t/384700/java/java/File-lastModified-windows-vs-linux. If we come into the situation where we compare timestamps written by different filesystems we may have to deal with it here.