add:    if (httpchannel.responseStatus == 304) return false;     if (httpchannel.responseStatus == 404) return false;  
context:     onAfterGet: function() {        var httpchannel = this.mChannel.QueryInterface(Components.interfaces.nsIHttpChannel);        try {            this.mEtag = httpchannel.getResponseHeader("ETag");        } catch(e) {            // No etag header. Now what?            this.mEtag = null;        }        this.mChannel = null;        return true;    },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/0defd389125b4b1ab8c53a084d478f9dd695fe02/calICSCalendar.js/buggy/calendar/providers/ics/calICSCalendar.js