title: Weird ssh behavior - ssh sets PROMPT_COMMAND in unknown place
body: <p>I've noticed recently weird behaviour of bash. It was reporting non-existing <code>preexec_set_exit</code> command or function. Small investigation showed that when I'm being logged through ssh <code>PROMPT_COMMAND</code> variable is set to following value:</p>
  
  <pre><code>   PROMPT_COMMAND=preexec_set_exit;preexec_invoke_cmd
  </code></pre>
  
  <p>It happens only on ssh, even when I'm logging into localhost.</p>
  
  <p>Tried to grep through all files in <code>~/</code> and in <code>/etc</code> but no luck</p>
  
  <p>I was installing and testing a while ago some tools and hacks from the net but can't remember what could cause the issue. Any ideas where this comes from or how to debug (and remove) it?</p>