$item['filefield_imce']['path'] has an absolute url and file is not located in database

I've got the error of

The selected file could not be used because the file does not exist in the database.

Because $item['filefield_imce']['file_path'] has an absolute url (starting with http://) and I don't find if it is due any setting, but I'm sure this case is not managed on function "filefield_source_imce_value", so I write a patch to manage it.