diff --git a/ethutil/big.go b/ethutil/big.go
index 8d7b3fe70e..07d1386e18 100644
--- a/ethutil/big.go
+++ b/ethutil/big.go
@@ -2,8 +2,6 @@ package ethutil
 
 import "math/big"
 
-var MaxInt256 *big.Int = BigD(Hex2Bytes("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"))
-
 // Big pow
 //
 // Returns the power of two big integers
diff --git a/vm/vm_debug.go b/vm/vm_debug.go
index 129ea1a590..05ae347f6b 100644
--- a/vm/vm_debug.go
+++ b/vm/vm_debug.go
@@ -394,7 +394,7 @@ func (self *DebugVm) RunClosure(closure *Closure) (ret []byte, err error) {
 			stack.Push(base)
 		case SIGNEXTEND:
 			back := stack.Pop().Uint64()
-			if back.Cmp(big.NewInt(31)) < 0 {
+			if back < 31 {
 				bit := uint(back*8 + 7)
 				num := stack.Pop()
 				mask := new(big.Int).Lsh(ethutil.Big1, bit)