diff -r 07c4f9bcb4d5 -r 160ebfb944a9 lemon/lp_utils.h
--- a/lemon/lp_utils.h	Wed Apr 18 16:34:40 2007 +0000
+++ b/lemon/lp_utils.h	Wed Apr 18 16:35:04 2007 +0000
@@ -886,7 +886,10 @@
           os << "+ ";
         }
         os << e.constComp() << " ";
-      } 
+      }
+      if (e.begin() == e.end() && e.constComp() == 0.0) {
+        os << "0 ";
+      }
     }
 
   protected: