Steps to reproduce:
1)Clean installation Liferay 6.1 GA3 Or 6.2 GA1
2)Login as administrator
3)Create Custom Fields for the type Document Library ex. 1 custom field text 2 custom field date
4)Go to Document and Media and create a new basic document. Just insert a title and set custom fields in a random way.
6)Go back to the uploaded document -> edit
7)Change custom fields value.
9)Custom fields are back to the first version and not updating.
Liferay 6.1 GA2 is not affected.