BlueZ, do not require authentication

Question

Hi,

I'm working with BlueZ 3.x. I have a linux embedded device and I need to send and receive files using the bluetooth technology, with Obex. (Note: BlueZ 4.x doesn't even compile on our specific platform.)

I don't need PIN authentication, I even don't want it. It must remain as simple as possible for the end user.

I tried to set security none in hcid.conf but it doesn't seem to work.

So my question is : is it possible ? How to do it ? Do some bluetooth devices (e.g. mobile phone) requires authentication anyway ?