Description:
------------
Using the resource inline in the uri works, (ie, 
ssh2.sftp://$session/path/to/file) but will throw a "supplied resource is not a 
valid SSH2 SFTP resource in .." warning on things like file_get_contents.


--
I found this bugreport in a note in the manual, original by stm555 at hotmail dot 
com

Test script:
---------------
$session = ssh2_connect('shell.example.com', 22);
ssh2_auth_agent($session, 'username');

$passwd = file_get_contents("ssh2.sftp://$session/etc/passwd");


Expected result:
----------------
There should be no warning when everything is peachy

Actual result:
--------------
Warning: file_get_contents(): supplied resource is not a valid SSH2 SFTP resource 
in /home/casper/projects/aaa/ssh2.php