Having experience with server side scripting.
Try looking up the name for the 'submit' button on the login page.
I know some sites might if (isset($_POST['submit'])).. to see if someone has 'submitted' a form.

(I went to face book and I found the form)

I revised your SOCKREAD code some..
Here is what the outmessage looks like:
var %out.message = email=test@email&pass=testpass&login=Login

Also when submitting more then one form value seperate them by a &
Example:
var %post = username=SuperMan007&passwd=kryptonite


on *:sockopen:FB:{
if ($sockerr) { echo 4 @FB -- Socket Error! -- }
echo 12 @FB -- Socket now open --

var %out.message = email=test@email&pass=testpass&login=Login

var %s = sockwrite -n $sockname
%s POST /login.php HTTP/1.1
%s Referer: http://www.facebook.com/index.php
%s Host: facebook.com
%s Content-Type: application/x-www-form-urlencoded
%s Content-Length: $len(%out.message)
%s Connection: Keep-Alive
%s Cache-Control: no-cache
%s
%s %out.message

echo 4 @FB -- end for now --
}


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