diff --git a/lib/http-proxy/index.js b/lib/http-proxy/index.js
index f86a7d8..7a5e1d2 100644
--- a/lib/http-proxy/index.js
+++ b/lib/http-proxy/index.js
@@ -104,7 +104,7 @@ function ProxyServer(options) {
     return ws[pass];
   });
 
-  this.on('error', this.onError.bind(this));
+  this.on('error', this.onError, this);
 
 }