After long searching for ways to do data migration, I finally found a use of Talend ETL :)(http://www.adempiere.com/Talend_Open_Studio). It has been there since 2010, can't believe I never find it! -_-"
I think it does solve my problem perfectly, so I made a tutorial just to share with community here @
I am no expert about ETL. comment / suggestions are really welcome!
nice tutorial, thx!