'Aborted' status in firebug Net panel with netcat proxy

Question

Hi,

For front-end debug purposes, I've set a netcat proxy in order to intercept HTTP requests, eg:

$ mkfifo /tmp/backpipe
$ while true; do nc -vv -l -k 12345 < /tmp/backpipe | tee -a requests.in | nc localhost 80 | tee -a requests.out > /tmp/backpipe; done

It works great but, in firebug, when accessing my web application on port 12345, I've got a red 'Aborted' status for some requests in the Net panel, causing some ressources not to be loaded (like some scripts or stylesheets...). However everything is OK on port 80.

What does this 'Aborted' status exactly mean?

PS: my browser's cache is disabled.

Thank you.