Index: include/mapnik/ctrans.hpp
===================================================================
--- include/mapnik/ctrans.hpp	(revision 690)
+++ include/mapnik/ctrans.hpp	(working copy)
@@ -73,6 +73,8 @@
          t_.forward(x,y);
          return command;
       }
+      
+      unsigned  num_points() { return geom_.num_points(); }
         
       void rewind (unsigned pos)
       {
Index: agg/include/agg_path_length.h
===================================================================
--- agg/include/agg_path_length.h	(revision 690)
+++ agg/include/agg_path_length.h	(working copy)
@@ -31,6 +31,9 @@
         double y2 = 0.0;
         bool first = true;
 
+        if( vs.num_points() <= 1 )
+            return 0.0;
+            
         unsigned cmd;
         vs.rewind(path_id);
         while(!is_stop(cmd = vs.vertex(&x2, &y2)))