//global background color variable
//set this to change the hover background color
var BACKGROUND_COLOR = '#ffffcc';

function trhover()
{
        //sets up all rows in all tables to have the hover effect.
        var tables = document.getElementsByTagName("table"), thisTable, thisRow, rowcount=0, tablecount=0;
        while (thisTable = tables[tablecount++])
        {
                while (thisRow = thisTable.rows[rowcount++])
                {
                        thisRow.onmouseover = turnOn;
                        thisRow.onmouseout = turnOff;
                }
        }
}
function turnOn()
{
        //this function sets the row's background color on mouseover
        this.style.backgroundColor = BACKGROUND_COLOR;
}
function turnOff()
{
        //this function sets the row's background color back to normal
        this.style.backgroundColor = '';
}


//set up the event handlers for the tables when the page loads
function tableInit()
{
        trhover();
}
window.onload = tableInit;