Fix bug where an attempt to run special interactive C++ examples could happen when C++ was not configured.
Fix bug where an attempt to run special interactive C++ examples could
happen when C++ was not configured.


svn path=/trunk/; revision=12044

FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot