function setIFrameHeight(_iframeId)
{    
    if (window.addEventListener) //firefox
    {          
        var _action=function()
        {       
            var _iframe=document.getElementById(_iframeId);
            if (!_iframe) return;
            _iframe.height=_iframe.contentDocument.body.scrollHeight;
            _iframe.onload=function()
            {
                if(this.contentDocument.body!=null);
                this.height=this.contentDocument.body.offsetHeight+16;
            }
        }
        window.addEventListener("load", _action, false);
    }
    else if (window.attachEvent) //IE
    {
        var _action=function()
        {        
            if (!document.getElementById(_iframeId)) return;
            document.getElementById(_iframeId).height=document.frames[_iframeId].document.body.scrollHeight;
            document.getElementById(_iframeId).onreadystatechange=function()
            {
                if (this.readyState=="complete")
                {
                    if(document.frames[_iframeId].document.body!=null)
                    this.height=document.frames[_iframeId].document.body.scrollHeight;
                }
            }
        }
        window.attachEvent("onload", _action);
    }
}
//setIFrameHeight('Main');