Thanks for your reply Shongrunden.
I`m afraid none of the fixes worked.
However, thanks to you and your reply I did some additional tests and I found a fix:
All the mirroring occured in group subclasses. When replacing the group tags with skinnable container tags it worked as it should.
I presume there is a bug in the group class causing this strange behaviour (?)
haha , used by my is sdk4.1, just do this:
override public function get layoutDirection():String
this is OK. but It took me about one day