// For more reference go to : http://blog.codesta.com/codesta_weblog/2007/12/net-gotchas---p.html
// This fix is for hitting the "Enter" key in a multiline textbox in Firefox.
function WebForm_FireDefaultButton(event, target) 
{
    //event.srcElement doesn't work in FF so we check whether
    //it or event.target exists, using whichever is returned
    var element = event.target || event.srcElement;       
    if (event.keyCode == 13 && !(element && (element.tagName.toLowerCase() == "textarea"))) 
    {    
        var defaultButton;
        if (__nonMSDOMBrowser) 
        {
            defaultButton = document.getElementById(target);
        } 
        else 
        {
            defaultButton = document.all[target];
        }
        if (defaultButton && typeof defaultButton.click != "undefined") 
        {            
            defaultButton.click();
            event.cancelBubble = true;
            if (event.stopPropagation) 
            {
                event.stopPropagation();
            }
            return false;
        }
    }
    return true;    
}