FB.UI using imaging staging - facebook

Question

I have a standard file-upload form, which I want to use to collect a user's image and than upload to Facebook.
If I post the upload form to the FB 'staging' url, I get the encoded staging reference - but when I try to launch a FB.UI() feed dialog, supplying the staging token as a "picture" parameter it fails?
Is the staging URL strictly for use in creating a graph object w/o using the dialog? And if I want do use the dialog do I have to upload the image somewhere else and than reference it ?
Here's my example:
$('#picture_upload').submit(function(e){
e.preventDefault();
$(this).attr('action',$(this).attr('action')+'?access_token='+accessToken);
$(this).ajaxSubmit({
success: function(response){
FB.ui(
{
method: 'feed',
name: 'Facebook Dialogs',
picture: response.uri,
caption: 'Reference Documentation',
description: 'Dialogs provide a simple, consistent interface for applications to interface with users.'
},
function(response) {
if (response && response.post_id) {
alert('Post was published.');
} else {
alert('Post was not published.');
}
}
);
} //call function after success
});
});
The response contains something like:
{"uri":"fbstaging://graph.facebook.com/staging_resources/MDAxMDE1MTU3NjIyNzExNzYwNA=="}
Which is obviously invalid as a picture parameter in the FB.UI function