Merge the mpl fixes for gcc 4.4. (But not the python ones). Refs #2069.
Merged revisions 48960 via svnmerge from https://svn.boost.org/svn/boost/trunk
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r48960 | rwgk | 2008-09-25 05:49:24 +0100 (Thu, 25 Sep 2008) | 1 line
boost/python, boost/mpl: gcc 4.4 compatibility (see http://svn.boost.org/trac/boost/ticket/2069)