function changeDivHeight() 
{
    //de hoogte aanpassen aan de hoogte van de client
    var h;
    if (self.innerHeight) // all except Explorer
    {
        h = self.innerHeight;
    }
    else if (document.documentElement && document.documentElement.clientHeight)
        // Explorer 6 Strict Mode
    {
        h = document.documentElement.clientHeight;
    }
    else if (document.body) // other Explorers
    {
        h = document.body.clientHeight;
    }
    h=h-205;
    document.getElementById('divMainText').style.height = h + "px";
}
onload = changeDivHeight;
onresize = changeDivHeight;