iPhone to Rails - ERROR Errno::ECONNRESET: Connection reset by peer

iPhone to Rails - ERROR Errno::ECONNRESET: Connection reset by peer

I have an iPhone app that talks to a Rails website and I've recently
started getting the following error after an HTTP GET to the rails website
from the iPhone:
ERROR Errno::ECONNRESET: Connection reset by peer
/home/user/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/webrick/httpserver.rb:56:in
`eof?'
/home/user/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/webrick/httpserver.rb:56:in
`run'
/home/user/.rvm/rubies/ruby-1.9.2-p290/lib/ruby/1.9.1/webrick/server.rb:183:in
`block in start_thread'
It only happens from the iPhone4S, and doesn't happen with the iPhone5, so
I'm guessing transaction speed might have something to do with it? The
HTTP GET finishes OK, with a status code = 200.
1) Anyone have any idea on what could be causing this?
2) Anyone have any idea on how to debug this?