var heightOfViewPort = document.viewport.getHeight() // prototypejs method
var bannerHeight = banner.offsetHeight;
var contentViewPortHeight = heightOfViewPort-banner.offsetHeight-message_list_hdr.offsetHeight;
var heightOfViewPort = document.viewport.getHeight() // prototypejs method
var bannerHeight = banner.offsetHeight;
var contentViewPortHeight = heightOfViewPort-banner.offsetHeight-message_list_hdr.offsetHeight;