function doJumpToPage(host,target,protocol,port) {
    
    if (typeof(port) == "undefined") {
        var port = document.location.port
    }
    if (typeof(target) == "undefined") {
        var target = "/" 
    }
    if (typeof(protocol) == "undefined") {
        var protocol = document.location.protocol 
    }
        var bits = document.location.host.split(".")
    if (bits.length > 1) {
        bits[0] = host
    }
    var url = protocol + "//" + bits.join(".") + ((port!="")?":" + port:"") + target
    document.location = url
    }