WriteThroughMode inactive on Table ?

Hello, I 've a small problem using a table to update my container

It seems that the 'writeThrough' mode is inactive in for the table object. I mean it seems to be always 'on'

For example, I configure my Table like this :

myTable_1().setEditable(true);
myTable_1().setWriteThrough(false);

I can edit the fields, but If I cancel the editing, without commiting the change, doing :

myTable_1().discard();
myTable_1().setEditable(false);

The changes are immediatly reflected in my table...

I tried to set the readThrough property to true also (just in case), but nothing change. The datas in the container are always updated whatever the writeThrough mode maybe...