diff --git a/lib/sailthru_util.js b/lib/sailthru_util.js
index 9f53788..4eba2e6 100644
--- a/lib/sailthru_util.js
+++ b/lib/sailthru_util.js
@@ -1,14 +1,20 @@
 (function() {
-  var SailthruUtil, md5;
-  md5 = require('hashlib').md5;
+  var SailthruUtil, crypto;
+  crypto = require('crypto');
   exports.SailthruUtil = SailthruUtil = (function() {
     function SailthruUtil() {}
     SailthruUtil.getSignatureHash = function(params, secret) {
-      return md5(SailthruUtil.getSignatureString(params, secret));
+      return SailthruUtil.md5(SailthruUtil.getSignatureString(params, secret));
     };
     SailthruUtil.getSignatureString = function(params, secret) {
       return secret + SailthruUtil.extractParamValues(params).sort().join('');
     };
+    SailthruUtil.md5 = function(data) {
+      var md5;
+      md5 = crypto.createHash('md5');
+      md5.update(data);
+      return md5.digest('hex');
+    };
     SailthruUtil.extractParamValues = function(params) {
       var k, temp, v, values;
       values = [];
diff --git a/package.json b/package.json
index 262ec90..7b22a43 100644
--- a/package.json
+++ b/package.json
@@ -13,7 +13,6 @@
     },
     "main": "./lib/sailthru.js",
     "dependencies": {
-        "hashlib": ">=1.0.0"
     },
     "dev-dependencies": {
         "nodeunit": ">=0.5.0",
diff --git a/src/sailthru_util.coffee b/src/sailthru_util.coffee
index 1af2d79..aa66ed8 100644
--- a/src/sailthru_util.coffee
+++ b/src/sailthru_util.coffee
@@ -1,12 +1,17 @@
-{md5} = require('hashlib')
+crypto  = require 'crypto'
 
 exports.SailthruUtil = class SailthruUtil
     @getSignatureHash: (params, secret) ->
-        return md5(SailthruUtil.getSignatureString params, secret)
+        return SailthruUtil.md5(SailthruUtil.getSignatureString params, secret)
 
     @getSignatureString: (params, secret) ->
         return secret + SailthruUtil.extractParamValues(params).sort().join('')
 
+    @md5: (data) ->
+        md5 = crypto.createHash('md5')
+        md5.update data
+        return md5.digest 'hex'
+
     @extractParamValues: (params) ->
         values = []
         for k,v of params