由于XML无效，jqGrid停留在Loading ...上

I have a form with a search box, when triggered the value typed in the input field is sent to a web service, the web service returns XML data to me which I feed into a jqGrid to display a list of results. I got the results to display properly, the problem I have is when no results matching the search criteria are found, when that happens the web service still returns an XML with the usual header but without any dataset. What happens is that the jqGrid displays the "Loading..." box and it stays like that indefinitely and the search feature wont work until the webpage is reloaded.I have a form with a search box, when triggered