fixed #23

lib/abi.js

@@ -211,6 +211,7 @@ var signedIsNegative = function (value) {
 /// Formats input right-aligned input bytes to int
 /// @returns right-aligned input bytes formatted to int
 var formatOutputInt = function (value) {
+    value = value || "0";
     // check if it's negative number
     // it it is, return two's complement
     if (signedIsNegative(value)) {
@@ -222,6 +223,7 @@ var formatOutputInt = function (value) {
 /// Formats big right-aligned input bytes to uint
 /// @returns right-aligned input bytes formatted to uint
 var formatOutputUInt = function (value) {
+    value = value || "0";
     return new BigNumber(value, 16);
 };