diff --git a/packages/accounts-oauth1-helper/oauth1_binding.js b/packages/accounts-oauth1-helper/oauth1_binding.js
index 4b4bcf11ce..011dd3708b 100644
--- a/packages/accounts-oauth1-helper/oauth1_binding.js
+++ b/packages/accounts-oauth1-helper/oauth1_binding.js
@@ -95,13 +95,13 @@ OAuth1Binding.prototype._getSignature = function(method, url, rawHeaders, access
 
   var signatureBase = [
     method,
-    encodeURIComponent(url),
-    encodeURIComponent(parameters)
+    self._encodeString(url),
+    self._encodeString(parameters)
   ].join('&');
 
-  var signingKey = encodeURIComponent(self._secret) + '&';
+  var signingKey = self._encodeString(self._secret) + '&';
   if (accessTokenSecret)
-    signingKey += encodeURIComponent(accessTokenSecret);
+    signingKey += self._encodeString(accessTokenSecret);
 
   return crypto.createHmac('SHA1', signingKey).update(signatureBase).digest('base64');
 };
@@ -132,14 +132,22 @@ OAuth1Binding.prototype._call = function(method, url, headers, params) {
 };
 
 OAuth1Binding.prototype._encodeHeader = function(header) {
+  var self = this;
   return _.reduce(header, function(memo, val, key) {
-    memo[encodeURIComponent(key)] = encodeURIComponent(val);
+    memo[self._encodeString(key)] = self._encodeString(val);
     return memo;
   }, {});
 };
 
+OAuth1Binding.prototype._encodeString = function(str) {
+  if(str == null || str == "") return "";
+
+  return encodeURIComponent(str).replace(/[!'()]/g, escape).replace(/\*/g, "%2A");
+};
+
 OAuth1Binding.prototype._getAuthHeaderString = function(headers) {
+  var self = this;
   return 'OAuth ' +  _.map(headers, function(val, key) {
-    return encodeURIComponent(key) + '="' + encodeURIComponent(val) + '"';
+    return self._encodeString(key) + '="' + self._encodeString(val) + '"';
   }).sort().join(', ');
 };
diff --git a/packages/http/httpcall_common.js b/packages/http/httpcall_common.js
index 101e8028f8..2b4513ef21 100644
--- a/packages/http/httpcall_common.js
+++ b/packages/http/httpcall_common.js
@@ -4,15 +4,22 @@ Meteor.http = Meteor.http || {};
 (function() {
 
   Meteor.http._encodeParams = function(params) {
+    self = this;
     var buf = [];
     _.each(params, function(value, key) {
       if (buf.length)
         buf.push('&');
-      buf.push(encodeURIComponent(key), '=', encodeURIComponent(value));
+      buf.push(self._encodeString(key), '=', self._encodeString(value));
     });
     return buf.join('').replace(/%20/g, '+');
   };
 
+  Meteor.http._encodeString = function(str) {
+    if(str == null || str == "") return "";
+
+    return encodeURIComponent(str).replace(/[!'()]/g, escape).replace(/\*/g, "%2A");
+  };
+
   Meteor.http._buildUrl = function(before_qmark, from_qmark, opt_query, opt_params) {
     var url_without_query = before_qmark;
     var query = from_qmark ? from_qmark.slice(1) : null;
diff --git a/packages/http/httpcall_tests.js b/packages/http/httpcall_tests.js
index edd0a29fbd..b809e8d8bd 100644
--- a/packages/http/httpcall_tests.js
+++ b/packages/http/httpcall_tests.js
@@ -294,7 +294,6 @@ testAsyncMulti("httpcall - headers", [
 
 testAsyncMulti("httpcall - params", [
   function(test, expect) {
-
     var do_test = function(method, url, params, opt_opts, expect_url, expect_body) {
       var opts = {};
       if (typeof opt_opts === "string") {
@@ -324,6 +323,8 @@ testAsyncMulti("httpcall - params", [
     do_test("GET", "/", {foo:"bar", fruit:"apple"}, "/?foo=bar&fruit=apple", "");
     do_test("POST", "/", {foo:"bar", fruit:"apple"}, "/", "foo=bar&fruit=apple");
     do_test("POST", "/", {foo:"bar", fruit:"apple"}, "/", "foo=bar&fruit=apple");
+    do_test("GET", "/", {'foo!':"bang!"}, {}, "/?foo%21=bang%21", "");
+    do_test("POST", "/", {'foo!':"bang!"}, {}, "/", "foo%21=bang%21");
     do_test("POST", "/", {foo:"bar", fruit:"apple"}, {
       content: "stuff!"}, "/?foo=bar&fruit=apple", "stuff!");
     do_test("POST", "/", {foo:"bar", greeting:"Hello World"}, {