Window.opener Not Working In Mozilla?

My parent window is dash.html. From this i call a pat.jsp file which is a child window to dash.html. I wrote a function in dash.html

function feed_refresh(){
getGlaceCompleteDashBoardResult(1);
}

this function getGlaceCompleteDashBoardResult(1); is included in a .js file in dash.html file. Now from the pat.jsp i call the feed_refresh() function on onunload=db_refreshfeed(); like this.

var db_refreshfeed = function(){
if(REQUEST_TYPE)
window.opener.feed_refresh();
}

This code working nice in IE but in mozilla it throws uncaught exception.