doc.scripts['setOnResizePositionWrapper'] = setOnResizePositionWrapper;

window.onload = function() { doc.runScripts(); };

function setOnResizePositionWrapper()
{
    positionWrapper();
    doc.setFunction(window, 'resize', positionWrapper);
}

function positionWrapper()
{
    if (doc.measure.height(doc.id('wrapper')) < doc.window.height())
    {
        var topOffset = doc.window.height() / 2 - doc.measure.height(doc.id('wrapper')) / 2;
        doc.id('wrapper').style.top = (doc.scroll.y() + 0) + topOffset + "px";
    }
}