Unexpected error in mod_passenger?

Question

Apache HTTP Server

Error log:

[ pid=9811 thr=3074652544 file=ext/apache2/Hooks.cpp:884 time=2013-02-18 11:58:22.889 ]: Unexpected error in mod_passenger: An error occurred while receiving HTTP upload data: The timeout specified has expired (70007)<br>
  Backtrace:<br>
     in 'boost::shared_ptr<Passenger::BufferedUpload> Hooks::receiveRequestBody(request_rec*)' (Hooks.cpp:1321)<br>
     in 'int Hooks::handleRequest(request_rec*)' (Hooks.cpp:585)<br>

1. An error occurs when trying to submit a completed web form
2. An error occurs if the client has a slow Internet connection
3. Timeout in apache2.conf is 3000 seconds
4. An error occurs on different browsers