[Building Sakai] Release assignment grades

[Ciellie]

Hallo

We ran into an interessting senario. We have a large site, over 300 students. 
The lecturer grade an assignment and use the select all button and release the 
grades, after the cut of date of the assignment. More than half of the 
students grades was released to the gradebook, but allot was not. If you 
manualy release the grade of a student that was'nt released previously it 
works. If we select all the assignmets and release it again the same students 
grades does'nt get released. If I compare a students assignment that was 
released and one that was'nt released its the same both have attached files 
and look the same. 

Is there some functionality that I'm missing

We are still on sakai 2.6.1 

Thanx
Ciellie