Error 0X80004005(NS_ERROR_FAILIURE)

I have a timer in my jsp which runs every 1 second to call a DWR method. The method works fine but When I stop the server(tomcat).. It starts throwing me error alerts -

Component returned failure code: Error 0X80004005(NS_ERROR_FAILURE) nsIXMLHttpRequest.send

If I can have a way to identify that the server has been stopped, I will be able to cancel the timer.

Please give any idea to overcome this problem gracefully avoiding these continuous alerts.

Thnx
Sanath