[jQuery] $_FILES and $.ajax function

[hcvitto]

hi
i'm trying to send a file uploaded thourgh a form to a php file with
$.ajax function.
In my php file i can grab the value of the file type input only if i
use tha $_POST method; if i use $_FILES nothing happens. Does anyone
know whether jquery $.ajax function supports this type of data in the
data otpion?
How do i do this?
I tried with processData: false with no use..

Thanks Vitto