File upload via non-browser REST call (using attachment_fu)

Hi everyone,

this might be a really stupid question but I have hit a wall here. I
already tried various different strategies but I really cannot find a
solution. The only thing which have not tried is to fake a browser
request, but I do not wanna go that far. So I hope I missed something :wink:

Ok, finally our problem:
We have an application which allows file attachments for a model. We
implemented this feature with attachment_fu. Now we have the case, that
another application (a native windows app) needs to access this feature
via the API. We can create the model with no problem. But when it comes
to uploading files and adding them as an attachment, we have no luck
with the calls. Any idea or link what we are missing here? We simply are
not able to upload/access the file (always a 500 or something similar).

Thank you very much,