diff --git a/ChangeLog.txt b/ChangeLog.txt
index 796a12bb..631b43d8 100755
--- a/ChangeLog.txt
+++ b/ChangeLog.txt
@@ -1,8 +1,18 @@
 
 ChangeLog for jsrsasign
 
+* Changes between 5.1.0 to 6.0.0 (2016-Sep-11)
+  - As of so much request to remove Node functions
+    in nodeutil.js, nodeutil.js have been removed from
+    jsrsasign.js package. Then it is moved to
+    new "jsrsasign-util" npm package.
+    Now "jsrsasign" will be CommonJS, Purescript,
+    Webpack and Browserify safe package.
+    Some sample Node.js scripts in "sample_node"
+    will be updated later.
+
 * Changes between 5.0.15 to 5.1.0 (2016-Sep-07)
-  - jwsjs 2.0.x to 2.1.0
+  - jwsjs 2.0.15 to 2.1.0
     - refactoring and API document update
     - addSignature, verifyAll, verifyNth method added
     - make addSignatureByHeaderKey, 
diff --git a/index.html b/index.html
index 0d22b6f4..ff282c0b 100755
--- a/index.html
+++ b/index.html
@@ -69,6 +69,12 @@ <h3>FEATURES</h3>
 
 <h3>NEWS</h3>
 <dl>
+<dt><b>2016-Sep-11</b>:
+<dd><a href="https://github.com/kjur/jsrsasign/releases/tag/6.0.0">
+Release 6.0.0</a> is now available.
+Now "jsrsasign" become "fs" safe so that it will be available 
+for CommonJS or Webpack.
+
 <dt><b>2016-Sep-03</b>:
 <dd><a href="slide_e/">Slides for jsrsasign introduction</a> is available.
 
diff --git a/jsrsasign-latest-all-min.js b/jsrsasign-latest-all-min.js
index 1259093c..1013a4eb 100644
--- a/jsrsasign-latest-all-min.js
+++ b/jsrsasign-latest-all-min.js
@@ -1,5 +1,5 @@
 /*
- * jsrsasign 5.1.0 (2016-09-08) (c) 2010-2016 Kenji Urushima | kjur.github.com/jsrsasign/license
+ * jsrsasign 6.0.0 (2016-09-11) (c) 2010-2016 Kenji Urushima | kjur.github.com/jsrsasign/license
  */
 
 /*
@@ -284,6 +284,3 @@ if(typeof KJUR=="undefined"||!KJUR){KJUR={}}if(typeof KJUR.jws=="undefined"||!KJ
 /*! jwsjs-2.1.0 (c) 2010-2016 Kenji Urushima | kjur.github.com/jsrsasign/license
  */
 if(typeof KJUR=="undefined"||!KJUR){KJUR={}}if(typeof KJUR.jws=="undefined"||!KJUR.jws){KJUR.jws={}}KJUR.jws.JWSJS=function(){var b=KJUR.jws.JWS;var a=KJUR.jws.JWS;this.aHeader=[];this.sPayload="";this.aSignature=[];this.init=function(){this.aHeader=[];this.sPayload=undefined;this.aSignature=[]};this.initWithJWS=function(d){this.init();var c=d.split(".");if(c.length!=3){throw"malformed input JWS"}this.aHeader.push(c[0]);this.sPayload=c[1];this.aSignature.push(c[2])};this.addSignature=function(c,f,k,i){if(this.sPayload===undefined||this.sPayload===null){throw"there's no JSON-JS signature to add."}var j=this.aHeader.length;if(this.aHeader.length!=this.aSignature.length){throw"aHeader.length != aSignature.length"}try{var d=KJUR.jws.JWS.sign(c,f,this.sPayload,k,i);var h=d.split(".");var l=h[0];var e=h[2];this.aHeader.push(h[0]);this.aSignature.push(h[2])}catch(g){if(this.aHeader.length>j){this.aHeader.pop()}if(this.aSignature.length>j){this.aSignature.pop()}throw"addSignature failed: "+g}};this.addSignatureByHeaderKey=function(f,c){var e=b64utoutf8(this.sPayload);var d=new KJUR.jws.JWS();var g=d.generateJWSByP1PrvKey(f,e,c);this.aHeader.push(d.parsedJWS.headB64U);this.aSignature.push(d.parsedJWS.sigvalB64U)};this.addSignatureByHeaderPayloadKey=function(f,e,c){var d=new KJUR.jws.JWS();var g=d.generateJWSByP1PrvKey(f,e,c);this.aHeader.push(d.parsedJWS.headB64U);this.sPayload=d.parsedJWS.payloadB64U;this.aSignature.push(d.parsedJWS.sigvalB64U)};this.verifyAll=function(f){if(this.aHeader.length!==f.length||this.aSignature.length!==f.length){return false}for(var e=0;e<f.length;e++){var d=f[e];if(d.length!==2){return false}var c=this.verifyNth(e,d[0],d[1]);if(c===false){return false}}return true};this.verifyNth=function(d,h,e){if(this.aHeader.length<=d||this.aSignature.length<=d){return false}var f=this.aHeader[d];var i=this.aSignature[d];var j=f+"."+this.sPayload+"."+i;var c=false;try{c=a.verify(j,h,e)}catch(g){return false}return c};this.verifyWithCerts=function(d){if(this.aHeader.length!=d.length){throw"num headers does not match with num certs"}if(this.aSignature.length!=d.length){throw"num signatures does not match with num certs"}var l=this.sPayload;var h="";for(var e=0;e<d.length;e++){var f=d[e];var g=this.aHeader[e];var n=this.aSignature[e];var c=g+"."+l+"."+n;var k=new KJUR.jws.JWS();try{var m=k.verifyJWSByPemX509Cert(c,f);if(m!=1){h+=(e+1)+"th signature unmatch. "}}catch(j){h+=(e+1)+"th signature fail("+j+"). "}}if(h==""){return 1}else{throw h}};this.readJWSJS=function(e){if(typeof e==="string"){var d=b.readSafeJSONString(e);if(d==null){throw"argument is not safe JSON object string"}this.aHeader=d.headers;this.sPayload=d.payload;this.aSignature=d.signatures}else{try{if(e.headers.length>0){this.aHeader=e.headers}else{throw"malformed header"}if(typeof e.payload==="string"){this.sPayload=e.payload}else{throw"malformed signatures"}if(e.signatures.length>0){this.signatures=e.signatures}else{throw"malformed signatures"}}catch(c){throw"malformed JWS-JS JSON object: "+c}}};this.getJSON=function(){return{headers:this.aHeader,payload:this.sPayload,signatures:this.aSignature}};this.isEmpty=function(){if(this.aHeader.length==0){return 1}return 0}};
-/*! nodeutil-1.0.0 (c) 2015 Kenji Urushima | kjur.github.com/jsrsasign/license
- */
-function readFileUTF8(a){return require("fs").readFileSync(a,"utf8")}function readFileHexByBin(c){var b=require("jsrsasign");var a=require("fs");return b.rstrtohex(a.readFileSync(c,"binary"))}function readFile(b){var a=require("fs");return a.readFileSync(b,"binary")}function saveFile(c,b){var a=require("fs");a.writeFileSync(c,b,"binary")}function saveFileBinByHex(e,b){var a=require("fs");var c=require("jsrsasign");var d=c.hextorstr(b);a.writeFileSync(e,d,"binary")};
diff --git a/npm/lib/footer.js b/npm/lib/footer.js
index 64bca3f0..8038a7e3 100755
--- a/npm/lib/footer.js
+++ b/npm/lib/footer.js
@@ -50,9 +50,4 @@ exports.asn1 = KJUR.asn1;
 exports.jws = KJUR.jws;
 exports.lang = KJUR.lang;
 
-exports.readFileUTF8 = readFileUTF8;
-exports.readFileHexByBin = readFileHexByBin;
-exports.readFile = readFile;
-exports.saveFile = saveFile;
-exports.saveFileBinByHex = saveFileBinByHex;
 
diff --git a/npm/package.json b/npm/package.json
index 8e9beb0a..74ab4289 100755
--- a/npm/package.json
+++ b/npm/package.json
@@ -1,6 +1,6 @@
 {
   "name": "jsrsasign",
-  "version": "5.1.0",
+  "version": "6.0.0",
   "description": "opensource free pure JavaScript cryptographic library supports RSA/RSAPSS/ECDSA/DSA signing/validation, ASN.1, PKCS#1/5/8 private/public key, X.509 certificate, CRL, CMS SignedData, TimeStamp and CAdES and JSON Web Signature(JWS)/Token(JWT)/Key(JWK).",
   "main": "lib/jsrsasign.js",
   "scripts": {
diff --git a/npm_util/Makefile b/npm_util/Makefile
new file mode 100755
index 00000000..bd67c177
--- /dev/null
+++ b/npm_util/Makefile
@@ -0,0 +1,10 @@
+all:
+	echo aaa
+
+aaa:
+	cat \
+	lib/header.js \
+	../min/nodeutil-1.0.min.js \
+	lib/footer.js \
+	> lib/jsrsasign-util.js
+
diff --git a/npm_util/README.md b/npm_util/README.md
new file mode 100755
index 00000000..f227b105
--- /dev/null
+++ b/npm_util/README.md
@@ -0,0 +1,26 @@
+jsrsasign-util
+=========
+
+This package provides supplementary functions for 'jsrsasign' such like file I/O utilities.
+
+Public page is http://kjur.github.com/jsrsasign .
+
+[github TOP](http://kjur.github.io/jsrsasign/)|[API doc](http://kjur.github.io/jsrsasign/api/)|[Wiki](https://github.com/kjur/jsrsasign/wiki)|[Node sample](https://github.com/kjur/jsrsasign/tree/master/sample_node)
+
+AVAILABLE FUNCTIONS
+-----------------------------
+
+- [readFile](http://kjur.github.io/jsrsasign/api/symbols/global__.html#readFile) : read file as binary string
+- [readFileHexByBin](http://kjur.github.io/jsrsasign/api/symbols/global__.html#readFileHexByBin) : read file as binary then convert it to hexadecimal string
+- [readFileUTF8](http://kjur.github.io/jsrsasign/api/symbols/global__.html#readFileUTF8) : read file as UTF-8 string
+- [saveFile](http://kjur.github.io/jsrsasign/api/symbols/global__.html#saveFile) : save file as binary string
+- [saveFileBinByHex](http://kjur.github.io/jsrsasign/api/symbols/global__.html#saveFileBinByHex) : convert a hexadecimal string to raw string then save it as file.
+
+EXAMPLE(1) SIGNATURE
+--------------------
+
+    > var rsu = require('jsrsasign-util');
+    > var rawString = rsu.readFile("bar.bin");
+    > rsu.saveFileBinByHex("foo.bin", "30143abb...");
+
+
diff --git a/npm_util/lib/footer.js b/npm_util/lib/footer.js
new file mode 100755
index 00000000..75d090e0
--- /dev/null
+++ b/npm_util/lib/footer.js
@@ -0,0 +1,7 @@
+
+exports.readFileUTF8 = readFileUTF8;
+exports.readFileHexByBin = readFileHexByBin;
+exports.readFile = readFile;
+exports.saveFile = saveFile;
+exports.saveFileBinByHex = saveFileBinByHex;
+
diff --git a/npm_util/lib/header.js b/npm_util/lib/header.js
new file mode 100755
index 00000000..bcb9cd61
--- /dev/null
+++ b/npm_util/lib/header.js
@@ -0,0 +1,2 @@
+/*! jsrsasign-util-1.0.0 (c) 2016 Kenji Urushima | kjur.github.com/jsrsasign/license
+ */
diff --git a/npm_util/lib/jsrsasign-util.js b/npm_util/lib/jsrsasign-util.js
new file mode 100644
index 00000000..8f492c58
--- /dev/null
+++ b/npm_util/lib/jsrsasign-util.js
@@ -0,0 +1,11 @@
+/*! jsrsasign-util-1.0.0 (c) 2016 Kenji Urushima | kjur.github.com/jsrsasign/license
+ */
+/*! nodeutil-1.0.0 (c) 2015 Kenji Urushima | kjur.github.com/jsrsasign/license
+ */
+function readFileUTF8(a){return require("fs").readFileSync(a,"utf8")}function readFileHexByBin(c){var b=require("jsrsasign");var a=require("fs");return b.rstrtohex(a.readFileSync(c,"binary"))}function readFile(b){var a=require("fs");return a.readFileSync(b,"binary")}function saveFile(c,b){var a=require("fs");a.writeFileSync(c,b,"binary")}function saveFileBinByHex(e,b){var a=require("fs");var c=require("jsrsasign");var d=c.hextorstr(b);a.writeFileSync(e,d,"binary")};
+exports.readFileUTF8 = readFileUTF8;
+exports.readFileHexByBin = readFileHexByBin;
+exports.readFile = readFile;
+exports.saveFile = saveFile;
+exports.saveFileBinByHex = saveFileBinByHex;
+
diff --git a/npm_util/package.json b/npm_util/package.json
new file mode 100755
index 00000000..b284725d
--- /dev/null
+++ b/npm_util/package.json
@@ -0,0 +1,28 @@
+{
+  "name": "jsrsasign-util",
+  "version": "1.0.0",
+  "description": "utilities for jsrsasign (kjur.github.io/jsrsasign) such like file utilities",
+  "main": "lib/jsrsasign-util.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/kjur/jsrsasign.git"
+  },
+  "keywords": [
+    "jsrsasign", "utilities", "file"
+  ],
+  "author": "Kenji Urushima",
+  "licenses": [
+    {
+      "type": "MIT",
+      "url": "https://raw.github.com/kjur/jsrsasign/master/LICENSE.txt"
+    }
+  ],
+  "bugs": {
+    "url": "https://github.com/kjur/jsrsasign/issues"
+  },
+  "dependencies": {
+  }
+}