diff --git a/ot/lp/network_simplex_simple.h b/ot/lp/network_simplex_simple.h
index 5d9304068..630b595a8 100644
--- a/ot/lp/network_simplex_simple.h
+++ b/ot/lp/network_simplex_simple.h
@@ -1507,7 +1507,7 @@ namespace lemon {
 			if( retVal == OPTIMAL){
                 for (int e = _search_arc_num; e != _all_arc_num; ++e) {
                     if (_flow[e] != 0){
-                        if (abs(_flow[e]) > EPSILON)
+                        if (fabs(_flow[e]) > _EPSILON) // change of the original code following issue #126
                             return INFEASIBLE;
                         else
                             _flow[e]=0;