Valentin,

Unfortunately I did not build nginx --with-debug, additionally it would be somewhat tedious and hard to replicate the issue.

However, if needed, I can recompile nginx on a development server and see if I can replicate this error condition with spdy enabled. However the setup would be tedious as it requires setting up SSL, etc. Can you think of an easier way to test this though? Maybe simply a PHP file that does something like:

<?php
sleep(300);
file_put_contents("request.log", date());
?>

Then call that from nginx with spdy enabled and see if it writes twice to the file request.log.