diff --git a/vm.go b/vm.go
index 9e1e83b0b5..a727d58e57 100644
--- a/vm.go
+++ b/vm.go
@@ -100,7 +100,7 @@ func (vm *Vm) ProcContract(tx *Transaction, block *Block, cb TxCallback) {
 
   Pow256 := BigPow(2, 256)
 
-  fmt.Printf("#   op   arg\n")
+  //fmt.Printf("#   op   arg\n")
 out:
   for {
     // The base big int for all calculations. Use this for any results.
@@ -113,7 +113,7 @@ out:
     if !cb(0) { break }
 
     if Debug {
-      fmt.Printf("%-3d %-4d\n", pc, op)
+      //fmt.Printf("%-3d %-4d\n", pc, op)
     }
 
     switch op {