logging in, posting comments and everything works.
but when logged in as admin and trying to edit a picture with picEditor, i see the picture, then i choose rotate 90° and 100% quality, click on "save" and get :
Proxy Error
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request POST /gallery/picEditor.php.
Reason: Document contains no data
Apache Server Port 80
How large is the picture you're trying to edit? It could be that your server is having problems handling the rotate/resize because of the file size.
Ccan you dupliate this error on a different machine?