diff --git a/package.json b/package.json
index 5db3639..a2d331f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "modbus-serial",
-  "version": "6.0.0",
+  "version": "6.0.1",
   "description": "A pure JavaScript implemetation of MODBUS-RTU (Serial and TCP) for NodeJS.",
   "main": "index.js",
   "scripts": {
diff --git a/ports/asciiport.js b/ports/asciiport.js
index 4921938..c1657d0 100644
--- a/ports/asciiport.js
+++ b/ports/asciiport.js
@@ -169,8 +169,6 @@ var AsciiPort = function(path, options) {
         }
     });
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -182,6 +180,8 @@ var AsciiPort = function(path, options) {
             return this._client.isOpen;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(AsciiPort, EventEmitter);
 
diff --git a/ports/c701port.js b/ports/c701port.js
index 8bc92cd..6ed55b8 100644
--- a/ports/c701port.js
+++ b/ports/c701port.js
@@ -104,8 +104,6 @@ var UdpPort = function(ip, options) {
         modbus.openFlag = false;
     });
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -117,6 +115,8 @@ var UdpPort = function(ip, options) {
             return this.openFlag;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(UdpPort, EventEmitter);
 
diff --git a/ports/rtubufferedport.js b/ports/rtubufferedport.js
index b718fc2..b6cf51d 100644
--- a/ports/rtubufferedport.js
+++ b/ports/rtubufferedport.js
@@ -77,8 +77,6 @@ var RTUBufferedPort = function(path, options) {
         }
     });
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -90,6 +88,8 @@ var RTUBufferedPort = function(path, options) {
             return this._client.isOpen;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(RTUBufferedPort, EventEmitter);
 
diff --git a/ports/tcpport.js b/ports/tcpport.js
index 44aed25..bd7e223 100644
--- a/ports/tcpport.js
+++ b/ports/tcpport.js
@@ -94,8 +94,6 @@ var TcpPort = function(ip, options) {
         handleCallback(had_error);
     });
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -107,6 +105,8 @@ var TcpPort = function(ip, options) {
             return this.openFlag;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(TcpPort, EventEmitter);
 
diff --git a/ports/tcprtubufferedport.js b/ports/tcprtubufferedport.js
index bea8360..3f93abf 100644
--- a/ports/tcprtubufferedport.js
+++ b/ports/tcprtubufferedport.js
@@ -111,8 +111,6 @@ var TcpRTUBufferedPort = function(ip, options) {
         handleCallback(had_error);
     });
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -124,6 +122,8 @@ var TcpRTUBufferedPort = function(ip, options) {
             return this.openFlag;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(TcpRTUBufferedPort, EventEmitter);
 
diff --git a/ports/telnetport.js b/ports/telnetport.js
index 469cfbc..bc1bc92 100644
--- a/ports/telnetport.js
+++ b/ports/telnetport.js
@@ -99,8 +99,6 @@ var TelnetPort = function(ip, options) {
         handleCallback(had_error);
     });
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -112,6 +110,8 @@ var TelnetPort = function(ip, options) {
             return this.openFlag;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(TelnetPort, EventEmitter);
 
diff --git a/ports/testport.js b/ports/testport.js
index 48993a4..89d4b08 100644
--- a/ports/testport.js
+++ b/ports/testport.js
@@ -31,8 +31,6 @@ var TestPort = function() {
     // simulate 16 coils / digital inputs
     this._coils = 0x0000; // TODO 0xa12b, 1010 0001 0010 1011
 
-    EventEmitter.call(this);
-
     /**
      * Check if port is open.
      *
@@ -44,6 +42,8 @@ var TestPort = function() {
             return true;
         }
     });
+
+    EventEmitter.call(this);
 };
 util.inherits(TestPort, EventEmitter);