diff --git a/lib/opFns.js b/lib/opFns.js
index 7f00f1a980..46eb91315e 100644
--- a/lib/opFns.js
+++ b/lib/opFns.js
@@ -122,22 +122,22 @@ module.exports = {
   },
   // 0x10 range - bit ops
   LT: function (a, b, runState) {
-    return new BN(a.cmp(b) === -1)
+    return new BN(a.cmp(b) === -1 ? 1 : 0)
   },
   GT: function (a, b, runState) {
-    return new BN(a.cmp(b) === 1)
+    return new BN(a.cmp(b) === 1 ? 1 : 0)
   },
   SLT: function (a, b, runState) {
-    return new BN(a.fromTwos(256).cmp(b.fromTwos(256)) === -1)
+    return new BN(a.fromTwos(256).cmp(b.fromTwos(256)) === -1 ? 1 : 0)
   },
   SGT: function (a, b, runState) {
-    return new BN(a.fromTwos(256).cmp(b.fromTwos(256)) === 1)
+    return new BN(a.fromTwos(256).cmp(b.fromTwos(256)) === 1 ? 1 : 0)
   },
   EQ: function (a, b, runState) {
-    return new BN(a.cmp(b) === 0)
+    return new BN(a.cmp(b) === 0 ? 1 : 0)
   },
   ISZERO: function (a, runState) {
-    return new BN(a.isZero())
+    return new BN(a.isZero() ? 1 : 0)
   },
   AND: function (a, b, runState) {
     return a.and(b)