diff --git a/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInOutGen.java b/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInOutGen.java
index c47eadf619..2e9d8e7c56 100644
--- a/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInOutGen.java
+++ b/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInOutGen.java
@@ -123,7 +123,7 @@ public class WInOutGen extends ADForm implements EventListener, ValueChangeListe
 			LayoutUtils.addSclass("status-border", statusBar);
 			south.setHeight("22px");
 			
-			executeQuery();
+			postQueryEvent();
 		}
 		catch(Exception ex)
 		{
@@ -376,6 +376,27 @@ public class WInOutGen extends ADForm implements EventListener, ValueChangeListe
 	    return sql.toString();
 	}
 	
+	private void postQueryEvent() 
+    {
+		Clients.showBusy(Msg.getMsg(Env.getCtx(), "Processing"), true);
+    	Events.echoEvent("onExecuteQuery", this, null);
+    }
+    
+    /**
+     * Dont call this directly, use internally to handle execute query event 
+     */
+    public void onExecuteQuery()
+    {
+    	try
+    	{
+    		executeQuery();
+    	}
+    	finally
+    	{
+    		Clients.showBusy(null, false);
+    	}
+    }
+    
 	/**
 	 *  Query Info
 	 */
@@ -457,7 +478,7 @@ public class WInOutGen extends ADForm implements EventListener, ValueChangeListe
 		}
 		else if (cmbDocType.equals(e.getTarget()))
 		{
-		    executeQuery();
+		    postQueryEvent();
 		    return;
 		}
 		
@@ -490,7 +511,7 @@ public class WInOutGen extends ADForm implements EventListener, ValueChangeListe
 			m_C_BPartner_ID = e.getNewValue();
 			fBPartner.setValue(m_C_BPartner_ID);	//	display value
 		}
-		executeQuery();
+		postQueryEvent();
 	}	//	vetoableChange
 
 
diff --git a/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInvoiceGen.java b/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInvoiceGen.java
index 0f84210fdd..57085d199e 100644
--- a/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInvoiceGen.java
+++ b/zkwebui/WEB-INF/src/org/adempiere/webui/apps/form/WInvoiceGen.java
@@ -362,6 +362,28 @@ public class WInvoiceGen extends ADForm
         
         return sql.toString();
     }
+    
+    private void postQueryEvent() 
+    {
+    	Clients.showBusy(Msg.getMsg(Env.getCtx(), "Processing"), true);
+    	Events.echoEvent("onExecuteQuery", this, null);
+    }
+    
+    /**
+     * Dont call this directly, use internally to handle execute query event 
+     */
+    public void onExecuteQuery()
+    {
+    	try
+    	{
+    		executeQuery();
+    	}
+    	finally
+    	{
+    		Clients.showBusy(null, false);
+    	}
+    }
+    
 	/**
 	 *  Query Info
 	 */
@@ -443,7 +465,7 @@ public class WInvoiceGen extends ADForm
 		}
 		else if (cmbDocType.equals(e.getTarget()))
         {
-            executeQuery();
+            postQueryEvent();
             return;
         }
 		//
@@ -468,7 +490,7 @@ public class WInvoiceGen extends ADForm
 			m_C_BPartner_ID = e.getNewValue();
 			fBPartner.setValue(m_C_BPartner_ID);	//	display value
 		}
-		executeQuery();
+		postQueryEvent();
 	}	//	vetoableChange
 
 	/**