Description:
------------
missing stream  (or user stream wrapper )support

Reproduce code:
---------------
<?
$im = imagecreate();
imagejpeg($im,'php://output'); // or imagejpeg($im,'var://myvar');
?>

Expected result:
----------------
image sent to stdout or into $myvar 

Actual result:
--------------
Warning: imagejpeg() [function.imagejpeg]: Unable to open 'php://output' for writing: No such file or directory in ...