diff --git a/o2web/source/o2_core/o2/widget/Dialog.js b/o2web/source/o2_core/o2/widget/Dialog.js
index 658ca58b235bbc7732e69d55439875b0a32bbd0e..e33421488b2f8e7b3ce094a18c6781b4c87c0099 100644
--- a/o2web/source/o2_core/o2/widget/Dialog.js
+++ b/o2web/source/o2_core/o2/widget/Dialog.js
@@ -453,6 +453,20 @@ o2.widget.Dialog = o2.DL = new Class({
             // //	this.content.setStyle("display", "block");
             // //this.fireEvent("postShow");
 
+			var pn = this.node.getOffsetParent();
+			var p = pn.getPosition();
+
+			var h = this.css.to.height.toInt();
+			var y = this.css.to.top.toInt();
+			y = y+p.y;
+
+			var ih = window.innerHeight.toInt();
+			if (h+y> ih){
+				y = ih-p.y-h-20;
+				if (y<0) y=0;
+				this.css.to.top = ""+y+"px";
+			}
+
 			this.morph.start(this.css.to).chain(function(){
 				if (this.titleText) this.getTitle();
 				if (this.button) this.getButton();