diff --git a/package.json b/package.json
index fc3f3e12d1..12aa389767 100644
--- a/package.json
+++ b/package.json
@@ -7,6 +7,7 @@
     "build": "mkdir -p build; browserify src/index.js -o build/app.js"
   },
   "devDependencies": {
+    "ethereumjs-block": "^1.2.2",
     "ethereumjs-vm": "^1.3.0",
     "merkle-patricia-tree": "^2.1.2",
     "ethereumjs-util": "^4.4.0",
diff --git a/src/universal-dapp.js b/src/universal-dapp.js
index 229af42aa3..0a0726d801 100644
--- a/src/universal-dapp.js
+++ b/src/universal-dapp.js
@@ -5,6 +5,7 @@ var ethJSUtil = require('ethereumjs-util');
 var EthJSTX = require('ethereumjs-tx');
 var EthJSAccount = require('ethereumjs-account');
 var ethABI = require('ethereumjs-abi');
+var EthJSBlock = require('ethereumjs-block');
 var web3 = require('./web3-adapter.js');
 
 function UniversalDApp (contracts, options) {
@@ -569,7 +570,7 @@ UniversalDApp.prototype.runTx = function( data, args, cb) {
                 data: new Buffer(data.slice(2), 'hex')
             });
             tx.sign(account.privateKey);
-            var block = new EthJS.Block({
+            var block = new EthJSBlock({
                 header: {
                     // FIXME: support coinbase, difficulty, number and gasLimit
                     timestamp: new Date().getTime() / 1000 | 0