diff --git a/pregelix/pregelix-example/src/main/java/edu/uci/ics/pregelix/example/client/Client.java b/pregelix/pregelix-example/src/main/java/edu/uci/ics/pregelix/example/client/Client.java
index 20435cd..9fb0958 100644
--- a/pregelix/pregelix-example/src/main/java/edu/uci/ics/pregelix/example/client/Client.java
+++ b/pregelix/pregelix-example/src/main/java/edu/uci/ics/pregelix/example/client/Client.java
@@ -72,7 +72,7 @@
         public int ckpInterval = -1;
 
         @Option(name = "-dyn-opt", usage = "whether to enable dynamic optimization -- for better performance", required = false)
-        public boolean dynamicOptimization = false;
+        public String dynamicOptimization = "false";
     }
 
     public static void run(String[] args, PregelixJob job) throws Exception {
@@ -124,7 +124,7 @@
     }
 
     private static void setJobSpecificSettings(PregelixJob job, Options options) {
-        job.setDynamicVertexValueSize(options.dynamicOptimization);
+        job.setEnableDynamicOptimization(Boolean.parseBoolean(options.dynamicOptimization));
         job.getConfiguration().setLong(PregelixJob.NUM_VERTICE, options.numVertices);
         job.getConfiguration().setLong(PregelixJob.NUM_EDGES, options.numEdges);
         job.getConfiguration().setLong(ShortestPathsVertex.SOURCE_ID, options.sourceId);