diff --git a/README.md b/README.md
index b7fbb9e..b52aa5e 100644
--- a/README.md
+++ b/README.md
@@ -51,12 +51,12 @@ Thus, care must be taken when serializing structures containing function.
 
 ## Format
 
-The output of `.serialize(..)` is a strict superset of standard JSON, 
+The output of `.serialize(..)` is a strict superset of [standard JSON](https://www.json.org/json-en.html), 
 while the input format is a bit more relaxed than in several details.
 
 Extensions to JSON:
 - Recursion
-- null types
+- undefined / NaN
 - BigInt
 - Map / Set
 - Function
diff --git a/package.json b/package.json
index edb4a50..406906c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ig-serialize",
-  "version": "1.0.4",
+  "version": "1.0.5",
   "description": "experimental extended json serializaion...",
   "main": "serialize.js",
   "scripts": {
diff --git a/serialize.js b/serialize.js
index c7ee84d..07fddc3 100644
--- a/serialize.js
+++ b/serialize.js
@@ -35,6 +35,7 @@
 *	position?
 *	(XXX move this note to diff.jx)
 *
+* XXX do a revision of the JSON standard for things I could have forgotten...
 *
 *
 **********************************************************************/
@@ -267,7 +268,7 @@ module.eJSON = {
 
 		0: 'number', 1: 'number', 2: 'number', 3: 'number', 4: 'number',
 		5: 'number', 6: 'number', 7: 'number', 8: 'number', 9: 'number',
-		'.': 'number', '-': 'number',
+		'.': 'number', '-': 'number', '+': 'number',
 
 		'[': 'array',
 		'{': 'object',
@@ -410,8 +411,11 @@ module.eJSON = {
 		var j = i+1
 		while(j < str.length
 				&& (str[j] == '.'
+					|| str[j] == 'e'
 					|| (str[j] >= '0'
 						&& str[j] <= '9'))){
+			if(str.slice(j, j+2) == 'e+'){
+				j++ }
 			j++ }
 		// BigInt...
 		if(str[j] == 'n'){
diff --git a/test.js b/test.js
index 9e5a1f0..0cba81f 100755
--- a/test.js
+++ b/test.js
@@ -45,6 +45,10 @@ var setups = test.Setups({
 		return ['123', json] },
 	'number-neg': function(assert){
 		return ['-123', json] },
+	//'number-pos': function(assert){
+	//	return ['+123', json] },
+	'number-exp': function(assert){
+		return ['1e+100', json] },
 	'number-zero': function(assert){
 		return ['0', json] },
 	'float-a': function(assert){
@@ -196,6 +200,8 @@ test.Cases({
 		// numbers/floats...
 		['.123', '0.123'],
 		['123.', '123'],
+		['+123', '123'],
+		['123e100', '123e+100'],
 
 		// string quotes...
 		["'abc'", '"abc"'],