diff --git a/core/vm/instructions.go b/core/vm/instructions.go
index 75f0dd5792..42c32c467a 100644
--- a/core/vm/instructions.go
+++ b/core/vm/instructions.go
@@ -778,10 +778,10 @@ func opCall(pc *uint64, interpreter *EVMInterpreter, contract *Contract, memory
 	args := memory.GetPtr(inOffset.Int64(), inSize.Int64())
 	fmt.Printf("args 0%x\n", args)
 
-	if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args, OvmSLOADMethodId) {
+	if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args[0:4], OvmSLOADMethodId) {
 		fmt.Println("SLOAD")
 	}
-	if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args, OvmSSTOREMethodId) {
+	if bytes.Equal(toAddr.Bytes(), OvmContractAddress) && bytes.Equal(args[0:4], OvmSSTOREMethodId) {
 		fmt.Println("SSTORE")
 	}
 	if value.Sign() != 0 {
diff --git a/tests/ovm_test.go b/tests/ovm_test.go
index c28c3e2f6c..3dd4b99658 100644
--- a/tests/ovm_test.go
+++ b/tests/ovm_test.go
@@ -10,6 +10,9 @@ import (
 	"github.com/ethereum/go-ethereum/core/vm/runtime"
 )
 
+var KEY = common.FromHex("0000000000000000000000000000000000000000000000000000000000000000")
+var VALUE = common.FromHex("0000000000000000000000000000000000000000000000000000000000000001")
+
 func mstoreBytes(bytes []byte) []byte {
 	output := make([]byte, len(bytes)*5)
 	for i, b := range bytes {
@@ -46,13 +49,14 @@ func TestOvm(t *testing.T) {
 	db := state.NewDatabase(rawdb.NewMemoryDatabase())
 	state, _ := state.New(common.Hash{}, db)
 	address := common.HexToAddress("0x0a")
-	code := append(
-		mstoreBytes(vm.OvmSLOADMethodId),
+	code := mstoreBytes(KEY)
+	code = append(code, mstoreBytes(vm.OvmSLOADMethodId)...)
+	code = append(code,
 		call(
 			vm.OvmContractAddress,
 			0,
 			0,
-			4,
+			36,
 			0,
 			0)...)