nginx 0.1.30 *) Bugfix: the worker process may got caught in an endless loop if the SSI was used. *) Bugfix: the response encrypted by SSL may not transferred complete. *) Bugfix: if the length of the response part received at once from proxied or FastCGI server was equal to 500, then nginx returns the 500 response code; in proxy mode the bug appeared in 0.1.29 only. *) Bugfix: nginx did not consider the directives with 8 or 9 parameters as invalid. *) Feature: the "return" directive can return the 204 response code. *) Feature: the "ignore_invalid_headers" directive.

--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -361,8 +361,9 @@ ngx_ssl_send_chain(ngx_connection_t *c, 
             return NGX_CHAIN_ERROR;
         }
 
-        if (n < 0) {
-            n = 0;
+        if (n == NGX_AGAIN) {
+            c->buffered = 1;
+            return in;
         }
 
         buf->pos += n;