diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/ValuePreference.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/ValuePreference.java
index 60b9c53734..7cf9b50d55 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/ValuePreference.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/ValuePreference.java
@@ -219,10 +219,10 @@ public class ValuePreference extends Window implements EventListener<Event>
 		
 		this.setClosable(true);
 		adwindowContent = findADWindowContent(ref);
-		if (adwindowContent != null) {
-			adwindowContent.showBusyMask();
+		if (adwindowContent != null) {			
 			ZkCssHelper.appendStyle(this, "position: absolute;");
 			adwindowContent.getComponent().getParent().appendChild(this);
+			adwindowContent.showBusyMask(this);
 			LayoutUtils.openOverlappedWindow(ref, this, "after_start");
 		} else {
 			AEnv.showCenterScreen(this);
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/adwindow/AbstractADWindowContent.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/adwindow/AbstractADWindowContent.java
index 401ad97383..c1b27ac7d6 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/adwindow/AbstractADWindowContent.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/adwindow/AbstractADWindowContent.java
@@ -104,6 +104,7 @@ import org.compiere.util.Env;
 import org.compiere.util.Msg;
 import org.compiere.util.Util;
 import org.compiere.util.WebDoc;
+import org.zkoss.zk.au.out.AuScript;
 import org.zkoss.zk.ui.AbstractComponent;
 import org.zkoss.zk.ui.Component;
 import org.zkoss.zk.ui.Executions;
@@ -908,8 +909,8 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 				hideBusyMask();
 			}
 		});
-		showBusyMask();
 		getComponent().getParent().appendChild(win);
+		showBusyMask(win);		
 		LayoutUtils.openOverlappedWindow(getComponent(), win, "middle_center");
 	}
 
@@ -951,8 +952,8 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 				focusToActivePanel();				
 			}
 		});
-    	showBusyMask();
-    	getComponent().getParent().appendChild(chat);    	
+    	getComponent().getParent().appendChild(chat);
+    	showBusyMask(chat);    	    	
     	LayoutUtils.openOverlappedWindow(getComponent(), chat, "middle_center");
     	chat.showWindow();
     }
@@ -1726,8 +1727,8 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 			});
         }
 
-        showBusyMask();
-        getComponent().getParent().appendChild(findWindow);        
+        getComponent().getParent().appendChild(findWindow);
+        showBusyMask(findWindow);                
         LayoutUtils.openEmbeddedWindow(toolbar, findWindow, "after_start");
 	}
 
@@ -2190,9 +2191,9 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 				hideBusyMask();
 				focusToActivePanel();
 			}
-		});
-		showBusyMask();
+		});		
 		getComponent().getParent().appendChild(messagePanel);
+		showBusyMask(messagePanel);
 		LayoutUtils.openOverlappedWindow(getComponent(), messagePanel, "middle_center");
 	}
 	//
@@ -2223,9 +2224,9 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 					ProcessModalDialog dialog = new ProcessModalDialog(AbstractADWindowContent.this, getWindowNo(), AD_Process_ID,table_ID, record_ID, true);
 					if (dialog.isValid()) {
 						dialog.setWidth("500px");
-						dialog.setBorder("normal");
-						showBusyMask();
+						dialog.setBorder("normal");						
 						getComponent().getParent().appendChild(dialog);
+						showBusyMask(dialog);
 						LayoutUtils.openOverlappedWindow(getComponent(), dialog, "middle_center");
 						dialog.focus();
 					}
@@ -2474,9 +2475,9 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 						boolean isProcessMandatory = true;
 						executeButtonProcess(wButton, startWOasking, table_ID, recordIdParam, isProcessMandatory);
 					}
-				});
-				showBusyMask();
+				});				
 				getComponent().getParent().appendChild(win);
+				showBusyMask(win);
 				LayoutUtils.openOverlappedWindow(getComponent(), win, "middle_center");
 				win.focus();
 				return;
@@ -2506,9 +2507,9 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 					window.setZindex(1000);
 					window.setMaximizable(true);
 					window.setSizable(true);
-					ZkCssHelper.appendStyle(window, "position: absolute; ");
-					showBusyMask();
+					ZkCssHelper.appendStyle(window, "position: absolute; ");					
 					getComponent().getParent().appendChild(window);
+					showBusyMask(window);
 					cf.showWindow();
 					LayoutUtils.openOverlappedWindow(getComponent(), window, "middle_center");
 					window.focus();
@@ -2601,11 +2602,22 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 	public void hideBusyMask() {
 		if (mask != null && mask.getParent() != null) {
 			mask.detach();
+			StringBuilder script = new StringBuilder("var w=zk.Widget.$('#");
+			script.append(getComponent().getParent().getUuid()).append("');w.busy=false;");
+			Clients.response(new AuScript(script.toString()));
 		}
 	}
 	
-	public void showBusyMask() {
+	public void showBusyMask(Window window) {
 		getComponent().getParent().appendChild(getMask());
+		StringBuilder script = new StringBuilder("var w=zk.Widget.$('#");
+		script.append(getComponent().getParent().getUuid()).append("');");
+		if (window != null) {
+			script.append("var d=zk.Widget.$('#").append(window.getUuid()).append("');w.busy=d;");
+		} else {
+			script.append("w.busy=true;");
+		}
+		Clients.response(new AuScript(script.toString()));
 	}
 
 	private void executeButtonProcess(final IProcessButton wButton,
@@ -2677,7 +2689,7 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 						onRefresh(true, false);						
 					}
 				});
-				showBusyMask();
+				showBusyMask(form);
 				LayoutUtils.openOverlappedWindow(getComponent(), form, "middle_center");
 				form.focus();
 			}
@@ -2692,9 +2704,9 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 			if (dialog.isValid())
 			{
 				dialog.setWidth("500px");
-				dialog.setBorder("normal");
-				showBusyMask();
+				dialog.setBorder("normal");				
 				getComponent().getParent().appendChild(dialog);
+				showBusyMask(dialog);
 				LayoutUtils.openOverlappedWindow(getComponent(), dialog, "middle_center");
 				dialog.focus();
 			}
@@ -2842,9 +2854,9 @@ public abstract class AbstractADWindowContent extends AbstractUIPart implements
 				public void onEvent(Event event) throws Exception {
 					hideBusyMask();
 				}
-			});
-			showBusyMask();
-			getComponent().getParent().appendChild(dialog);			
+			});			
+			getComponent().getParent().appendChild(dialog);
+			showBusyMask(dialog);
 			LayoutUtils.openOverlappedWindow(this.getComponent(),dialog,"middle_center");
 		}
 		
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WBinaryEditor.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WBinaryEditor.java
index cf6145671a..f402f84234 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WBinaryEditor.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WBinaryEditor.java
@@ -162,9 +162,9 @@ public class WBinaryEditor extends WEditor
 			});			
 			adwindow = ADWindow.findADWindow(getComponent());
 			if (adwindow != null) {
-				ADWindowContent content = adwindow.getADWindowContent();
-				content.showBusyMask();
+				ADWindowContent content = adwindow.getADWindowContent();				
 				content.getComponent().getParent().appendChild(dialog);
+				content.showBusyMask(dialog);
 				LayoutUtils.openOverlappedWindow(content.getComponent().getParent(), dialog, "middle_center");
 			} else {
 				AEnv.showWindow(dialog);
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WStringEditor.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WStringEditor.java
index 4b89fdfac6..dc9bbebcb0 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WStringEditor.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/editor/WStringEditor.java
@@ -248,7 +248,7 @@ public class WStringEditor extends WEditor implements ContextMenuListener
 			if (adwindowContent != null) 
 			{
 				adwindowContent.getComponent().getParent().appendChild(dialog);
-				adwindowContent.showBusyMask();
+				adwindowContent.showBusyMask(dialog);
 				LayoutUtils.openOverlappedWindow(adwindowContent.getComponent().getParent(), dialog, "middle_center");
 			}
 			else
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/ExportAction.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/ExportAction.java
index c511151682..9e31f8303c 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/ExportAction.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/ExportAction.java
@@ -133,9 +133,9 @@ public class ExportAction implements EventListener<Event>
 			vb.appendChild(confirmPanel);
 			confirmPanel.addActionListener(this);
 		}
-
-		panel.showBusyMask();
+		
 		panel.getComponent().getParent().appendChild(winExportFile);
+		panel.showBusyMask(winExportFile);
 		LayoutUtils.openOverlappedWindow(panel.getComponent(), winExportFile, "middle_center");
 		winExportFile.addEventListener(DialogEvents.ON_WINDOW_CLOSE, this);
 	}
diff --git a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/FileImportAction.java b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/FileImportAction.java
index 50894dc2f2..1e6aee95fb 100644
--- a/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/FileImportAction.java
+++ b/org.adempiere.ui.zk/WEB-INF/src/org/adempiere/webui/panel/action/FileImportAction.java
@@ -195,9 +195,9 @@ public class FileImportAction implements EventListener<Event>
 			vb.appendChild(confirmPanel);
 			confirmPanel.addActionListener(this);
 		}
-
-		panel.showBusyMask();
+		
 		panel.getComponent().getParent().appendChild(winImportFile);
+		panel.showBusyMask(winImportFile);
 		LayoutUtils.openOverlappedWindow(panel.getComponent(), winImportFile, "middle_center");
 		winImportFile.addEventListener(DialogEvents.ON_WINDOW_CLOSE, this);
 	}
diff --git a/org.adempiere.ui.zk/js/window.js b/org.adempiere.ui.zk/js/window.js
index baaabad1d6..b6bc23dd7c 100644
--- a/org.adempiere.ui.zk/js/window.js
+++ b/org.adempiere.ui.zk/js/window.js
@@ -3,3 +3,38 @@ function _idempiere_popup_window(refid, windowid, position) {
 	var window = zk(windowid);
 	window.position(ref.$n(), position);
 }
+
+zk.override(zk.Widget.prototype, "canActivate",
+	function () {
+	    var b = this.$canActivate.apply(this, arguments);
+	    if (b) {
+	    	if (zk.currentModal) {
+	    		return true;
+	    	}
+			var wgt = this;
+			while (wgt) {
+				if (wgt.busy) {
+					if (wgt.busy.className == 'zul.wnd.Window') {
+						if (zUtl.isAncestor(wgt.busy, this)) {
+							return true;
+						} else {
+							wgt.busy.focus(0);
+							return false;
+						}				 		
+					} else {
+						jq.focusOut();
+					}
+					return false;
+				}
+				if (wgt.className == 'zul.wnd.Window') {
+					if (wgt.getMode() == 'overlapped') {
+						return true;
+					}
+				}
+				wgt = wgt.parent;
+			}
+			return true;
+		} else {
+			return false;
+		}
+	});