Boost 1.31 compatibility fix.
Boost 1.31 compatibility fix.

svn path=/trunk/libavg/; revision=1452

th3infinity/libavg,libavg/libavg,scotty007/libavg,hoodie/libavg,hoodie/libavg,yyd01245/libavg,scotty007/libavg,hoodie/libavg,th3infinity/libavg,yyd01245/libavg,scotty007/libavg,scotty007/libavg,libavg/libavg,yyd01245/libavg,th3infinity/libavg,th3infinity/libavg,hoodie/libavg,libavg/libavg,yyd01245/libavg,libavg/libavg