g1smd - 11:48 am on Jan 18, 2013 (gmt 0)
What he probably meant by that, is probably explained by looking at this confusing scenario:
5.3.21 is dated 2013-01-17
5.4.10 is dated 2012-12-20
Although by looking at the date, version 5.3.21 was produced more recently, in actual fact the 5.4.x versions are the ones with the more up-to-date feature set (as shown by the higher version numbers e.g. 5.4 vs. 5.3).