Authoring information Date & time is wrong!!

Trying to post new content with the YUI module activated and it always gives me the date and time wrong, why?!

I uninstalled it, now date and time is perfectly well.

What is the problem, anybody solved it?

I tried resetting "Location of YUI library" in "admin/settings/yui" to default instead of "sites/default/files/lib" but this didn't solve the bug. It still shows -1 day from current, also time is about 3-4 hours less. After working with it for days, sometimes it changes my posts to -1 month!!!

Weird, any help?!