diff --git a/lib/Client/ReadStream.js b/lib/Client/ReadStream.js
index e5b07f2..5329ab2 100644
--- a/lib/Client/ReadStream.js
+++ b/lib/Client/ReadStream.js
@@ -32,7 +32,8 @@ ReadStream.prototype._transform = function (chunk, encoding, next) {
 	while (this.pending.length >= 6) {
 		var pkg_len = this.pending.readUInt16BE(4) + 6;
 
-		if (this.pending.length < pkg_len) return next();
+		if (this.pending.length < 8)       return next(); // safety precaution
+		if (this.pending.length < pkg_len) return next(); // not all data yet
 
 		var data = this.pending.slice(8, pkg_len);
 		var pkg  = {
diff --git a/lib/Server/ReadStream.js b/lib/Server/ReadStream.js
index 3c6ce77..104f106 100644
--- a/lib/Server/ReadStream.js
+++ b/lib/Server/ReadStream.js
@@ -32,7 +32,8 @@ ReadStream.prototype._transform = function (chunk, encoding, next) {
 	while (this.pending.length >= 6) {
 		var pkg_len = this.pending.readUInt16BE(4) + 6;
 
-		if (this.pending.length < pkg_len) return next();
+		if (this.pending.length < 8)       return next(); // safety precaution
+		if (this.pending.length < pkg_len) return next(); // not all data yet
 
 		var data = this.pending.slice(8, pkg_len);
 		var pkg  = {
diff --git a/package.json b/package.json
index bdc6370..26d1da3 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name"            : "modbus-tcp",
-  "version"         : "0.4.7",
+  "version"         : "0.4.8",
   "description"     : "Modbus TCP/IP",
   "main"            : "lib/Modbus.js",
   "repository"      : "http://github.com/dresende/node-modbus-tcp.git",