diff --git a/pkg/vm/stack.go b/pkg/vm/stack.go
index 4f4db751e..183f6eac6 100644
--- a/pkg/vm/stack.go
+++ b/pkg/vm/stack.go
@@ -127,7 +127,9 @@ func (e *Element) Bytes() []byte {
 		if t.value {
 			return []byte{1}
 		}
-		return []byte{0}
+		// return []byte{0}
+		// FIXME revert when NEO 3.0 https://github.com/nspcc-dev/neo-go/issues/477
+		return []byte{}
 	default:
 		panic("can't convert to []byte: " + t.String())
 	}
diff --git a/pkg/vm/vm_test.go b/pkg/vm/vm_test.go
index 2eedf0ffa..059bc0afd 100644
--- a/pkg/vm/vm_test.go
+++ b/pkg/vm/vm_test.go
@@ -1033,7 +1033,9 @@ func TestSIZEBool(t *testing.T) {
 	vm.estack.PushVal(false)
 	runVM(t, vm)
 	assert.Equal(t, 1, vm.estack.Len())
-	assert.Equal(t, makeStackItem(1), vm.estack.Pop().value)
+	// assert.Equal(t, makeStackItem(1), vm.estack.Pop().value)
+	// FIXME revert when NEO 3.0 https://github.com/nspcc-dev/neo-go/issues/477
+	assert.Equal(t, makeStackItem(0), vm.estack.Pop().value)
 }
 
 func TestARRAYSIZEArray(t *testing.T) {