filter subgrids crm 2011 - 'setParameter': object is null or undefined

I am trying to filter subgrids based on a lookup field on the form. Could anyone explain why i get this error message:

Any advices is welcomed

Thank you.

The code:

function updateSubGrid() {
//This will get the related products grid details and store in a variable.
var related = Xrm.Page.ui.controls.get("AssociatedActivities") ;  
//Initializing the lookup field to store in an array.
var lookupfield = new Array;
//Get the lookup field
lookupfield = Xrm.Page.getAttribute("regardingobjectid").getValue();
//This will get the lookup field guid if there is value present in the lookup
if (lookupfield != null) {
	var lookupid = lookupfield[0].id;
}
//Else the function will return and no code will be executed.
else {
	return;
}
//This method is to ensure that grid is loaded before processing.
if (related ==null || related.readyState != "complete")
{
//This statement is used to wait for 2 seconds and recall the function until the grid is loaded.
	setTimeout("updateSubGrid()", 2000);
	return; 
}
//This is the fetch xml code which will retrieve all the order products related to the order selected for the case.
var fetchXml = "<fetch version=’1.0' output-format=’xml-platform’ mapping=’logical’ distinct=’false’>";
fetchXml += "<entity name=’activitypointer’>";
fetchXml += "<attribute name=’subject’/> ";
fetchXml += "<attribute name= ’statecode’/>";
fetchXml += "<attribute name=’prioritycode’/>";
fetchXml += "<attribute name= ’modifiedon’/>";
fetchXml += "<attribute name= ’activityid’/>"; 
fetchXml += "<attribute name= ’instancetypecode’/>";
fetchXml += "<order attribute=’modifiedon’ descending=’false’ />"; 
//fetchXml += "<link-entity name=’’ from=’’ to=’’ alias=’aa’>";
fetchXml += "<filter type=’and’>";
	fetchXml +="<filter type='or'>";
	     fetchXml += "<condition attribute=’statecode’ value=’” + lookupid + “‘ operator='eq'/>";
	    fetchXml += "<condition attribute=’statecode’ value='1' operator='eq'/>";
//fetchXml += “<condition attribute=’salesorderid’ operator=’eq’ uiname=’Order Name’ uitype=’salesorder’ value=’” + lookupid + “‘ />”;
 
					fetchXml += "</filter>";
				fetchXml += "</link-entity>";
			fetchXml += "</entity>";
	fetchXml += "</fetch>";
//Setting the fetch xml to the sub grid.
related.control.setParameter("fetchXml", fetchXml);
//This statement will refresh the sub grid after making all modifications.
related.control.refresh();
}