Thread:Extension talk:ChapTimeline/Garbled dates

I am using MediaWiki 1.22.3, Semantic MediaWiki 1.9.1.1 and ChapTimeline 0.1 (cloned with Git). I am getting dates on the wrong day, moved ahead of one month. For example, 2014/1/1 is shown on 2014/2/1. What can I do to troubleshoot this issue? Thank you.