diff --git a/lib/server/pipe.js b/lib/server/pipe.js
index e86e65ba..57bfbed4 100644
--- a/lib/server/pipe.js
+++ b/lib/server/pipe.js
@@ -24,7 +24,7 @@
     function create(params) {
         var gzip, read, write, isFsWrite,
             p               = params,
-            func            = Util.exec.ret(p.callback),
+            func            = p.callback,
             options         = {
                 bufferSize: 4 * 1024
             };
@@ -71,11 +71,16 @@
     }
     
     function on(event, emitter, callback) {
-        var listeners   = emitter.listeners(event),
-            indexOf     = listeners.indexOf(callback);
+        var isSet,
+            listeners   = emitter.listeners(event),
+            callbackStr = '' + callback;
         
-        if (!~indexOf)
-            emitter.once(event, callback);
+        isSet   = listeners.some(function(func) {
+            return '' + func === callbackStr;
+        });
+        
+        if (!isSet)
+            emitter.on(event, callback);
     }
     
     /**