title: Using concurrently 2 versions of boost
body: <p>I'm using RHEL 5.3, which is shipped with gcc 4.1.2 and boost 1.33.
  There're some features I want, that are missing in the boost 1.33. 
  Therefore the thought was to upgrade to fresh boost release 1.43. </p>
  
  <ol>
  <li><p>Is it possible to use concurrently some header-only library(s) from boost 1.43 and the rest from 1.33? For example I want to use unorded_map, which is missing in boost 1.33.</p></li>
  <li><p>Is it possible to use concurrently binary boost libraries from different releases?</p></li>
  </ol>