diff --git a/node_modules/kaefer/lib/version.js b/node_modules/kaefer/lib/version.js
index ecdfc9b4..0b3793ea 100644
--- a/node_modules/kaefer/lib/version.js
+++ b/node_modules/kaefer/lib/version.js
@@ -2,6 +2,6 @@ define(function(require, exports, module) {
 
 // on each backwards incompatible protocol change the version number must be
 // increased
-exports.protocol = 8;
+exports.protocol = 9;
 
 });
\ No newline at end of file
diff --git a/node_modules/kaefer/package.json b/node_modules/kaefer/package.json
index 5fd74395..2b11575a 100644
--- a/node_modules/kaefer/package.json
+++ b/node_modules/kaefer/package.json
@@ -8,8 +8,8 @@
         "email": "fabian@c9.io"
     }],
     "dependencies": {
-        "engine.io": "~1.3.1",
-        "engine.io-client": "~1.3.1",
+        "engine.io": "~1.5.1",
+        "engine.io-client": "~1.5.1",
         "amd-loader": "*"
     },
     "devDependencies": {
diff --git a/package.json b/package.json
index 563df54d..b917e82e 100644
--- a/package.json
+++ b/package.json
@@ -18,8 +18,8 @@
         "connect": "~2.12.0",
         "debug": "~0.7.4",
         "ejs": "~0.8.3",
-        "engine.io": "~1.3.1",
-        "engine.io-client": "~1.3.1",
+        "engine.io": "~1.5.1",
+        "engine.io-client": "~1.5.1",
         "eslint": "git://github.com/cloud9ide/eslint.git#e2d052aafd81ea0aa6d1d4fd9f88f3613e386160",
         "http-error": "~0.0.5",
         "less": "~1.5.1",