Conflict with the File Picker module

Hello,

I'm testing Image field crop, and there is no problem to crop an image except when I want to delete my image already cropped and save my node.
In this case, there is a conflict with the File Picker module (6.x-1.3) and after saving my node, I have these messages in the "List" tab:
- This file does not belong to you.
- File not found.
The url is www.mydomain.com/filepicker/list

Finally, I can't delete my image cropped and I can't upload another image !!
Could you help me?
Thanks a lot