Attached Files = 0 octet ???

Hi,

I'm working on the latest version of Nuxeo and I have to face to a strange issue. All attached files (in the
"files" menu of a document) appears with 0 octet (empty).... I really thing they didn't upload
correctly.. How can I solve it ? Where can it come from ? On the basic configuration, I don't have this
problem. My Nuxeo is configured with PostgreSQL.

Remark : All imported files are perfectly readable, the problem is just located on the attached files

Thx in advance ! ;)