diff --git a/js/ViewerPanel.js b/js/ViewerPanel.js
index 0e43d6a..d19424b 100644
--- a/js/ViewerPanel.js
+++ b/js/ViewerPanel.js
@@ -29,7 +29,9 @@ Zarafa.plugins.fileviewer.ViewerPanel = Ext.extend(Ext.Panel, {
 	title: '',
 
 	/**
-	 * @cfg {Boolean} autoResize This flag specifies if the panel gets automatically resized if the window size has changed.
+	 * @cfg {Boolean|Ext.Component} autoResize This flag specifies if the panel gets automatically resized if the window size has changed.
+	 * If it is set to true the panel will listen on the Window update event. Otherwise it will listen to the component
+	 * resize event.
 	 * Defaults to false.
 	 */
 	autoResize: false,
@@ -57,6 +59,14 @@ Zarafa.plugins.fileviewer.ViewerPanel = Ext.extend(Ext.Panel, {
 
 		if (Ext.isDefined(config.autoResize)) {
 			this.autoResize = config.autoResize;
+		} else {
+			this.autoResize = false;
+		}
+
+		if (Ext.isDefined(config.defaultScale)) {
+			this.defaultScale = config.defaultScale;
+		} else {
+			this.defaultScale = 0.8;
 		}
 
 		Ext.applyIf(config, {
@@ -90,8 +100,16 @@ Zarafa.plugins.fileviewer.ViewerPanel = Ext.extend(Ext.Panel, {
 	 * @private
 	 */
 	initEvents: function () {
-		if (this.autoResize) {
+		if (this.autoResize === true) {
 			Ext.EventManager.onWindowResize(this.resizePanel, this);
+		} else if(this.autoResize !== false) {
+			this.autoResize.on('resize', this.resizePanel, this);
+
+			// save old autoscroll value and disable autoscrolling
+			if(Ext.isDefined(this.autoResize.autoScroll)) {
+				this.autoResize.initialAutoScrollValue = this.autoResize.autoScroll;
+				this.autoResize.setAutoScroll(false);
+			}
 		}
 	},
 
@@ -100,19 +118,35 @@ Zarafa.plugins.fileviewer.ViewerPanel = Ext.extend(Ext.Panel, {
 	 * @private
 	 */
 	onDestroy: function () {
-		if (this.autoResize) {
+		if (this.autoResize === true) {
 			Ext.EventManager.removeResizeListener(this.resizePanel, this);
+		} else if(this.autoResize !== false) {
+			this.autoResize.un('resize', this.resizePanel, this);
+
+			// re-enable autoscrolling if it was enabled before
+			if(Ext.isDefined(this.autoResize.autoScroll)) {
+				this.autoResize.setAutoScroll(this.autoResize.initialAutoScrollValue);
+			}
 		}
+
 		Zarafa.plugins.fileviewer.ViewerPanel.superclass.onDestroy.call(this, arguments);
 	},
 
 	/**
+	 * This functions resizes the panel to the given width. It will be called on the resize event if autoResize is enabled.
 	 *
 	 * @param {Number} width The window width.
 	 * @param {Number} height The window height.
 	 * @private
 	 */
 	resizePanel: function (width, height) {
+		// the element event will pass more arguments
+		// than the window resize event
+		if(arguments.length > 2) {
+			var autoResizeElement = arguments[0];
+			width = autoResizeElement.getInnerWidth();
+			height = autoResizeElement.getInnerHeight();
+		}
 		this.setWidth(width * this.defaultScale);
 		this.setHeight(height * this.defaultScale);
 
diff --git a/manifest.xml b/manifest.xml
index 4d37869..d827941 100755
--- a/manifest.xml
+++ b/manifest.xml
@@ -2,7 +2,7 @@
 <!DOCTYPE plugin SYSTEM "manifest.dtd">
 <plugin version="2">
 	<info>
-		<version>1.0</version>
+		<version>1.0.1</version>
 		<name>fileviewer</name>
 		<title>PDF and ODF attachments preview</title>
 		<author>Christoph Haas</author>