diff -Naur HippoDraw-1.21.3/python/PyDataSource.cxx HippoDraw-1.21.3.new/python/PyDataSource.cxx
--- HippoDraw-1.21.3/python/PyDataSource.cxx	2007-08-24 18:19:16.000000000 -0400
+++ HippoDraw-1.21.3.new/python/PyDataSource.cxx	2008-06-01 14:22:46.000000000 -0400
@@ -444,9 +444,14 @@
 copy_direct ( boost::python::numeric::array array,
 	      std::vector<double > & col )
 {
+#ifdef HAVE_NUMARRAY
   T * data = reinterpret_cast < T * > ( num_util::data ( array ) );
   int size = num_util::size ( array );
   std::copy ( data, data+ size, back_inserter( col ) );
+#else
+  throw std::runtime_error ("HippoDraw was not built with "
+			     "numeric Python support" );
+#endif
 }
 
 void 
@@ -454,6 +459,7 @@
 extractVector ( boost::python::numeric::array array,
 		std::vector<double> & col )
 {
+#ifdef HAVE_NUMARRAY
   PyArray_TYPES type = num_util::type ( array );
 
   if ( num_util::iscontiguous ( array ) &&
@@ -515,7 +521,11 @@
 	  col.push_back ( boost::python::extract < double > ( result ) );
 	}
       }
-  } 
+  }
+#else
+  throw std::runtime_error ("HippoDraw was not built with "
+			     "numeric Python support" );
+#endif
 }
 
 PyDataSource *