Index: Common/vtkLine.cxx
===================================================================
RCS file: /cvsroot/VTK/VTK/Common/vtkLine.cxx,v
retrieving revision 1.84
diff -u -r1.84 vtkLine.cxx
--- a/Common/vtkLine.cxx	2 May 2004 04:33:58 -0000	1.84
+++ b/Common/vtkLine.cxx	29 Jun 2004 01:07:06 -0000
@@ -273,6 +273,10 @@
   //
   num = p21[0]*(x[0]-p1[0]) + p21[1]*(x[1]-p1[1]) + p21[2]*(x[2]-p1[2]);
   denom = vtkMath::Dot(p21,p21);
+  if (denom == 0.0)
+    {
+    return -1.0;
+    }
 
   // trying to avoid an expensive fabs
   tolerance = VTK_TOL*num;

Index: Common/vtkTriangle.cxx
===================================================================
RCS file: /cvsroot/VTK/VTK/Common/vtkTriangle.cxx,v
retrieving revision 1.107
diff -u -r1.107 vtkTriangle.cxx
--- a/Common/vtkTriangle.cxx	2 May 2004 04:33:59 -0000	1.107
+++ b/Common/vtkTriangle.cxx	29 Jun 2004 01:07:00 -0000
@@ -244,6 +244,10 @@
         {
         dist2 = vtkLine::DistanceToLine(x,pt1,pt2,t,closestPoint);
         }
+      if (dist2Line1 == -1.0 || dist2Line2 == -1.0 || dist2 == -1.0)
+        {
+        return -1;
+        }
       }
     return 0;
     }