diff --git a/repository/TiddlyWiki/Tiddler.class.st b/repository/TiddlyWiki/Tiddler.class.st
index 9b9f26d..5eec807 100644
--- a/repository/TiddlyWiki/Tiddler.class.st
+++ b/repository/TiddlyWiki/Tiddler.class.st
@@ -28,8 +28,8 @@ Class {
 
 { #category : #'instance creation' }
 Tiddler class >> nowLocal [
-	^ (ZTimestampFormat fromString: '20010203160506700') 
-			format: (ZTimestamp fromString: Time nowLocal  asDateAndTime asString)
+	^ ((ZTimestampFormat fromString: '20010203160506700') 
+			format: (ZTimestamp fromString: Time nowLocal asDateAndTime asString)) copyFrom: 1 to: 17
 ]
 
 { #category : #accessing }
@@ -38,12 +38,12 @@ Tiddler >> asDictionary [
 	response := Dictionary new
 		at: 'title' put: self title;
 		at: 'text' put: self text;
-		at: 'created' put: self created asString;
+		at: 'created' put: self created;
 		at: 'tags' put: self tags;
 		at: 'type' put: self type;
 		at: 'creator' put: self creator;
 		at: 'modifier' put: self modifier;
-		at: 'modified' put: self modified asString;
+		at: 'modified' put: self modified;
 		at: 'bag' put: self bag;
 		at: 'revision' put: self revision;
 		yourself.
@@ -110,7 +110,7 @@ Tiddler >> caption: anObject [
 { #category : #accessing }
 Tiddler >> created [
 
-	^ created asZTimestamp ifNil: [ created := self class nowLocal ]
+	^ created ifNil: [ created := self class nowLocal ]
 ]
 
 { #category : #accessing }
@@ -348,8 +348,7 @@ Tiddler >> markdownLinksAsWikiText [
 { #category : #accessing }
 Tiddler >> modified [
 
-	modified ifNil: [ ^ modified ].
-	^ modified asZTimestamp
+	^ modified
 ]
 
 { #category : #accessing }
diff --git a/repository/TiddlyWiki/TiddlyWiki.class.st b/repository/TiddlyWiki/TiddlyWiki.class.st
index a71c7f1..992f4f0 100644
--- a/repository/TiddlyWiki/TiddlyWiki.class.st
+++ b/repository/TiddlyWiki/TiddlyWiki.class.st
@@ -58,9 +58,9 @@ TiddlyWiki >> changesAfter: aDateString [
 	| recent created modified wiki aDate |
 	aDate := aDateString asZTimestamp.
 	wiki := self contentTiddlersWithoutLargeTiddlers.
-	created := wiki select: [ :tiddler | tiddler created > aDate ].
+	created := wiki select: [ :tiddler | tiddler created asZTimestamp > aDate ].
     modified := wiki select: [ :tiddler | tiddler modified isNotNil 
-    	and: [ tiddler modified > aDate ] ].
+    	and: [ tiddler modified asZTimestamp > aDate ] ].
     
     recent := OrderedCollection new.
 	recent