HTTP wrapper does not support writeable connections

Hi,
I just update my WordPress to 3.6, and I got this errormessage:

Warning: fopen(http://www.renegadeterrior.hu/wp-content/uploads/2013/01/szahara_2-60×60.jpg) [function.fopen]: failed to open stream: HTTP wrapper does not support writeable connections in /data/www/up.econsilium.hu/wp-includes/class-wp-image-editor.php on line 342

But If I upload back the previous version of my WP, I don’t get this warning…
What is the problem?