function checkBox( boxSID )
{
        for( var i = 0 ; i < document.forms[0].SID.length ; i++ )
        {
                if( document.forms[0].SID[i].value == boxSID )
                {
                        document.forms[0].SID[i].checked =
                                !document.forms[0].SID[i].checked ;
                }
        }
}